







Finding the area of a regular polygon 
20070504 

From Dana: We are trying to figure the square footage of a tetradecagon....sort of a round house with 14 sides that are 8 ft' in length. It has a height of 9 ft. How do we figure the square footage of this? Answered by Stephen La Rocque. 





A square and a triangle 
20181203 

From Livvy: a square with a perimeter of 48 and a triangle with a perimeter of 38. when they are joined they make a pentagon. please find the perimeter
how can you find the perimeter of this. could you please help me? Answered by Penny Nom. 





Two regular pentagons 
20180319 

From Kip: The ratio of the corresponding apothems of two similar regular pentagons is 5:7 What is the ratio of their areas? Answered by Penny Nom. 





Needing the area of an irregular Pentagon 
20171206 

From Dale: I'm needing to find the square footage of an irregular pentagon.
I've seen the other questions similar to this one, but without a great deal of difficulty can't get you the angle degrees, or the length between opposing angles.
I'm hoping that a different bit of information can help. So here goes:
The longest side is 67ft long.
One of its legs is 39ft long, and the other is 18ft long.
The leg off of the other end of the 39ft leg is 35ft long.
The leg off of the other end of the 18ft is 49ft long, and meets the other end of the 35ft side.
The information that I DO have, which I'm hoping makes the difference, is that the 39ft and the 18ft sides are parallel.
Also, while the angles at each end of the 67ft side are not right angles, they are fairly close to it,
approximately 80 degrees at the 39 ft side corner, and 100 degrees at the 18ft side corner.
Dale. Answered by Harley Weston. 





A barn roof 
20160529 

From Joe: Is it possible to build a barn roof (irregular pentagon?) with a 12' base and the other 4 sides 4' each? Thanks. Answered by Penny Nom. 





A pentagon inscribed in a circle 
20150530 

From Victoria: find the area of a regular pentagon inscribed in a circle with radius 3 units Answered by Penny Nom. 





The area of a pentagon 
20141104 

From Gracie: i really need help with this problem in my math book, will you help?
"Derrick drew regular pentagon with side lengths of 8 centimeters.
He divided the pentagon into 5 identical triangles, and measured the
height of one of the triangles to be 5.5 centimeters. Find the area of
the pentagon."
this really makes no sense to me. Can you help me with anything
to make it easier?
THANKS!!!!! Answered by Penny Nom. 





Drawing a pentagon 
20130506 

From jacob: hello. i am trying to draw a template for a project. but i don't have a
protractor. i'm trying to draw a normal pentagon with 2cm sides. what
i'm trying to figure out is the distance in centimeters from point a, to c,
in a straight line. this is needed so that i can measure and create the
shape without a protractor, and keep the angles and sides correct.
if you can help me with the measurement, or help me another way,
any help would be greatly appreciated. thank you. Answered by Penny Nom. 





A 5 pointed star in a circle 
20120805 

From wiljohn: find the area of a 5 pointed star in the circle with a radius of 12.517 Answered by Chris Fisher. 





Drawing an isosceles triangle 
20120510 

From Nazrul: How can I draw an isosceles triangle whose each angle adjacent to the base is twice the vertex angle? Answered by Chris Fisher. 





The interior angles of a pentagon 
20110310 

From Daima: I need help!
The interior angle of a pentagon i s5 ( I hope ) or 540 degrees.
The interior angle of a pentagon is what? Explain to me please.
Daima Answered by Penny Nom. 





A regular pentagon 
20091214 

From Jamie: A regular pentagon is inscribed in a circle of radius 4.5 cm.
Determine its perimeter and area to one decimal place!
Thank YOU ! :) Answered by Penny Nom. 





Two similar pentagons 
20091116 

From louis: The lengths of five sides of a pentagon are 1,3,5,7,and 12 units. If the length of the longest side of a similar polygon is 18 units, find the perimeter of the larger pentagon. I think I figured it out Not sure though. Answered by Penny Nom. 





An area problem 
20090830 

From Amber: Area of hexagon ABCDEF with the vertices (3,0) (7,0) (9,2) (7,4) (3,4) (1,0) Answered by Harley Weston. 





A pentagon inscribed in a circle 
20090729 

From Faisal: O is the center of the circle. Sides AB and AE are equal. Angle B = 95,
angle C = 130, angle D = 138. Find angles A and E.
Diagram is attached.
Best,
Faisal Answered by Chris Fisher. 





The interior angles of a pentagon 
20090420 

From Mary: If four interior angles of a fivesided figure pentagon measure 100 degrees each, what will the fifth angle measure? Answered by Harley Weston. 





The perimeter of a pentagon 
20090407 

From Malysa: A pentagon has an area of 1400 cm squared. Determine its perimeter. Answered by Harley Weston. 





Symmetries of a polyhedron 
20090302 

From Vincent: I want to ask is there a formula to find out the number of axes of rotation & plane
of reflection of a 3D figure, like pentagon, pyramid? Answered by Chris Fisher. 





A word problem about a regular pentagon 
20081116 

From Sandra: If the area of a regular pentagon is A=1.720a^2, in which a is one of the sides. Find the area of a regular pentagon with a side that measures 50cm. Answered by Chris Fisher and Penny Nom. 





A fivesided coin 
20080629 

From carla: A new fivesided coin is to be made in the shape of figure 8.6
The point A on the circumference of the coin is the centre of arc CD, which has a radius of 2cm
Similarly B is the centre of arc DE, and so on.
Find the area of one face of the coin. Answered by Harley Weston. 





The area of a regular pentagon 
20080602 

From Jenna: I would like to know if there is a formula to find the area of a regular Pentagon that is not inscribed in a circle only apothem and side length are given. Answered by Penny Nom. 





The angles of an irregular pentagon 
20080520 

From victoria: The sum of the measure of two angles is 240. If the remaining angles are congruent, what is the measure of each angle? Answered by Penny Nom. 





The area of an irregular pentagon 
20080402 

From shane: i Need to find out what this adds up to i have a diagram of a pentagon and all the shides are different how do i do this if the sides are 5100,7200,7200,7400,7400 Answered by Harley Weston. 





A fish tank in the shape of an irregular pentagon 
20080329 

From richie: i am building a fish tank. it is going to be an irregular pentagon. the sides are going to be
24"
24"
8"
8"
32"(approximately)
there will 3 right angles A, B, E
my question is how to figure out the degree of the angles that are not right angles (C,D)? Answered by Chris Fisher. 





A pentagon inscribed in a circle 
20080319 

From Elaine: My question as written on my homework is: Given a pentagon inscribed in a circle of radius r, determine a) the angle between any two sides of the pentagaon b) the perimeter of the pentagaon c) the area of the pentagon. I know this kind of counts as three questions, so if you can only answer one, that's okay. Any help will be much appreciated. Thanks! Answered by Stephen La Rocque. 





A three dimensional object 
20080304 

From Briana: what is the 3d term for pentagon? like a circle is a shhere? Answered by Penny Nom. 





Two regular pentagons 
20080227 

From Shirley: Regular pentagon QRSTU has a side length of 12 centimeters and an area of
248 square centimeters. Regular pentagon VWXYZ has a perimeter of 140
centimeters.
I need to find its area. Answered by Stephen La Rocque. 





A triangle and a pentagon 
20071208 

From Olivia: A regular pentagon has an area of 800 square centimetres. What is the area of the triangle extended from one side of the pentagon? Answered by Stephen La Rocque. 





The area of a regular pentagon 
20071101 

From sarah: i'm trying to find the area of a regular pentagon with 200m sides, ive split it into 5 triangles so i dont know either sizes of the lengths and i need to find the height!
how? Answered by Penny Nom. 





All five angles of a pentagon ABCDE are equal 
20070804 

From Jerry: All five angles of a pentagon ABCDE are equal. The diagonals AC, AD and BD have the same length. Prove that all five sides of the pentagon are equal in length. Answered by Penny Nom. 





Find the area of a regular pentagon inscribed in a circle 
20070803 

From Tracy: Can you please help me with finding the area of a regular pentagon inscribed in a circle using the Pythagorean theorem. The radius of the circle is 5 cm and each side AB = BC = CD = DE = EA = 6 cm. Answered by Stephen La Rocque, Leeanne Boehm and Chris Fisher. 





Area of a star in a regular pentagon with side length 10cm 
20070724 

From Chetna: A regular pentagon with side 10 cm has a star drawn within (the vertices match).
What is the area of the star? Answered by Stephen La Rocque. 





Area of a pentagonal lot 
20070509 

From Mimi: I would like to know the square footage of a pentagon with the
following measurements:
Property is .43 of an Acre
Front: 57.11'
NW: 105.78'
S: 120'
SE: 145'
E: 102.86'
I don't want you to try to show me how to work thru the problem since
I will never comprehend it. For some reason, I am unable to perform these
kinds of equations. I will greatly appreciate your help. Answered by Penny Nom. 





The area of an irregular pentagon 
20070414 

From Steven: I have been given a coursework in which i have to investigate various shapes to find the one that would give the largest area with 1000m perimeter.
I'm stuck in a part where i have to calculate the area of a irregular pentagon. i don't know where to start from. I can make up the length of all the sides (5 sides), so long they add up to 1000, but i'm not quite sure what to do after that. Answered by Penny Nom. 





Reducing the over all size of a irregular pentagon 
20070411 

From Gilbert: I'm having trouble figuring out how to reduce the over all size of a irregular pentagon.
The pentagon I'm trying to reduce has 2 right angles adjacent to each other.
Basically the shape of a house. I have width, length of the legs and the height of the peak.
But cannot figure out how to get the size of a reduced version that keeps the same proportion
and angles.
Thanks
Gilbert Answered by Penny Nom. 





An irregular pentagon 
20070411 

From reg: Hi, i have been given an irregular pentagon in which i have to work out the area.
I have been told to make three triangles and then work out the area of these triangles and then add them up.
I require your help because i have the length of two sides of one of the triangle  how do i work out the other side?
I have not been provided with any angles  can i make the angles up? Answered by Penny Nom. 





The area of an irregular pentagon 
20070326 

From grace: hi I am doing graphics and need to find the area of the section given to us (it is just drawn). the sides measure 15m, 35.4m, 5m, 17.8m, 35.7m. the angle between the 15m side and the 35.4m side is 17degrees, the angle between the 35.4m side and the 5m side is 73degrees. the angle between the 5m side and the 17.8m side is 151degrees, the angle between the 17.8m side and the 35.7m side is 90degrees and the angle between the 35.7m side and the 15m side is 95degrees. if you could tell me the area i would be extremely grateful. thanks very much. Answered by Penny Nom. 





An irregular pentagon 
20070308 

From kelly: If I have a pentagon with 2 sides of length 5 and one with a length of 2, what are the lengths of other 2 sides? Answered by Stephen La Rocque. 





The net for a pentagonal pyramid 
20070305 

From MaKayla: How many bases does the net for a pentagonal pyramid have? Answered by Penny Nom. 





A pentagon inscribed in a circle 
20070222 

From Amanda: Find the formula for calculating the length of the side of a pentagon given the radius of the circle that encloses it. Once you find the formula, find the length of the side of a pentagon which is enclosed in a circle 12 cm in diameter. So I need to know the formula, and the length of the side of the pentagon. Thank you!! Answered by Penny Nom. 





The area for a pentagon 
20070209 

From nicole: how do you find the area for a pentagon Answered by Stephen La Rocque. 





Splitting a 5 acre piece of property 
20070125 

From John: I have a 5 acre piece of property that I wish to split into 5 individual 1 acre parcels. The 5 acre parcel 1s 660 feet in length and 330 feet in width. The first two parcels are 264'x165', but I am asking for help getting the perimeters of the last 3 lots, one of which is a irregular pentagon. All of the one acre parcels must have an area of 43,560 square feet each. Answered by Penny Nom. 





A regular pentagonal pyramid 
20070125 

From Vickifazio: a regular pentagonal pyramid has a base perimeter of 1,085 ft. How long is one side of the base? Answered by Stephen La Rocque. 





How do the perimeters of the two pentagons compare? 
20070102 

From Robert: If the area of one pentagon is eightyone times the area of another pentagon, how do the perimeters of the two pentagons compare? Answered by Penny Nom. 





The area of regular pentagon inscribed in a circle 
20061012 

From Admire: i need help on how to find area of regular pentagon inscribed in a circle of radius 8cm Answered by Stephen La Rocque and Penny Nom. 





The area of a pentagon 
20060511 

From Jessica: i have to find the area of a pentagon ABCDE whose vertices are A (2,5), B (2,2),C(2,4), D(5,2) and E(4,2) Answered by Stephen La Rocque. 





The area of a pentagon 
20060201 

From Edward: I am working on finding the Sq. ft of a pentagon. I saw another question like it but I am lost. I have a pentagon that is 6ft on every side what is the Sq Footage of that pentagon? Answered by Penny Nom. 





The area of a pentagon 
20050824 

From Susan: I need to calculate the square footage of a regular pentagon (all angles are equal). Each side is 16 feet long. Answered by Penny Nom. 





An irregular pentagon 
20050223 

From Tony: Please help me with confirming the area in square footage of the irregular pentagon
My Name is Tony and I am working on understanding the square footage as calculated in the drawing. I also believe this is a secondary level question.
I saw the example http://mathcentral.uregina.ca/QQ/database/QQ.09.03/dana2.html and would appreciate how you worked through the problem, but couldn't find the calculations so that I could adapt them to my sizes. Answered by Penny Nom. 





The area of a pentagon 
20040606 

From Dana: HELLO, I NEED HELP IN DETERMINING THE SIZE OF A PENTAGON.
one side is 280',from both ends of the 280 'section,we have 300' lengths,from one of these 300' sections we have a 118' length,which goes over to a length of 228',will this be enough info. or should i provide more. thanks Answered by Penny Nom. 





Sum of the angles in a pentagon 
20040311 

From Ashish: What is the sum of all the measures of the angles of a Pentagon Answered by Penny Nom. 





Constructions of polygons 
20030103 

From Garrett: Our teacher just finished the constructions unit, and he mentioned briefly about odd sided figures such as pentagons and septagons, only that they're very hard. My question is, how do you draw, with a compass and a straight edge, a pentagon and septagon? Answered by Chris Fisher. 





Construct a pentagon 
20021212 

From Mary: We were wondering what the instructions/formula, stepbystep, is to make a pentagon. Answered by Chris Fisher and Penny Nom. 





A polygon with five sides 
20011003 

From A student: I was asked a question in 5th grade today that goes: i am a polygon with five sides and 2 right angles what do i look like and what is my name Answered by Penny Nom. 





Area of a regular polygon 
20010501 

From Carl: What is the formula for finding the area of a regular Hexagon and a regular Pentagon Answered by Penny Nom. 





An irregular polygon 
20010209 

From Jason: I have a 5 sided irregular polygon I am trying to figure out the area of. There are no right angles in the polygon as far as I can tell. I do not know any angles. Answered by Chris Fisher. 





Angles in Polygons 
19990121 

From Jen:
 How do u find the interior angles of a pentagon when you are given 4 of the angles and you need to find the fifth?
 If you are given the measure of each exterior angle of a regular polygon, how do you figure out how many sides the polygon has?
 i need all information on polygons and how to find their angles!!!
Answered by Jack LeSage. 

