







An enclosure for some remote control boats 
20171003 

From Roberto: I am trying to build a "ring" for our remote control boats, using irrigation pipe.
I'd like to use full 20' long sticks for the long sides and use eight of what we call
45s, which are actually 135' fittings to make the six short sides. If I know the length
of the two long sides, what would be the formula to find the exact lengths of the short sides?
Thank you. Answered by Penny Nom. 





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 hexagon with different side lengths 
20140516 

From Grace: Sorry if this is a simple question, but I can't seem to understand how to solve it. I am Trying to find the area of a hexagon with measurements 6x7x6x6x7x6, or 2 sets of opposing sides with 6, and one set with 7. Thank you. Answered by Penny Nom. 





The area of an irregular octagon 
20131118 

From zafar: if i have a rectangular octagon then how i can find its area
1. The length of rectangle is 42 and the width is 21 and and the base length is 4212 =30 i mean the
length of base =30 Answered by Penny Nom. 





The fourth side of an irregular polygon 
20130201 

From Emran: I have a irregular polygon. I know 3 of the 4 sides, and 2 of the angles. AB is 285, BC is 149, and CD is 310. Angle B is 135 degrees. and Angle C is 45 degrees. Is there a formula to solve for the final side? Thanks. Answered by Penny Nom. 





The area of an irregular hexagon 
20120320 

From Jacob: I am having trouble finding the area of an irregular hexagon with 5 right angles.
It has 5 given sides, with the lengths as follows:
8.2 ft.
6 ft.
4.5 ft.
2.2 ft.
6 and one third ft. Answered by Chris Fisher. 





The volume of an irregular tetrahedron 
20120222 

From Brittany: If I am given an irregular tetrahedron with the coordinates of the 4 points how do I find the volume? For example I am asked to find the volume and only given the points A(4,3,5), B(2,1,2), C(0,5,0), and D(2,0,0) can you shown me the working and formular to find the volume? Answered by Robert Dawson. 





Regular and irregular polygons 
20110310 

From thaera: the difference between regular shape and irregular shapes. Answered by Penny Nom. 





An irregular hexagon 
20110209 

From Emma: Hello,
I have math question about how to find the area of an irregular hexagon.
It is shaped like a backwards L and the side lengths are as follows
11cm
8cm
5cm
5cm
6 cm
3cm
Can you please help me find the area of this?
Emma Answered by Penny Nom. 





The area of a hexagon 
20100728 

From Katie: Hi i have to find the area of a hexagon with only the side length 2cm given
would you be able t help? Answered by Walter Whiteley. 





An irregular octagon 
20100309 

From Gayle: Question from Gayle:
I am building an irregular shaped octagon wooden box.
The measurements are 291/2 inches by 211/2 inches.
Sides are 12 inches.
It will be 36 inches high.
What would the cutting angles degrees be? Answered by Harley Weston. 





An irregular quadrilateral 
20091029 

From riya: what is irregular quadrilateral? 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. 





Cubic yards in an Irregular Shape 
20090608 

From ron: hi i have a berm 100'w x200'L at the base and 9'tall the top is 85'L x 20'w i would to find out how many cubic yards are in the pile and the formula Answered by Janice Cotcher. 





Surface area of an irregular shape 
20081215 

From Patrick: An irregular shaped object (lets say a gold nugget, not smooth with
pockets) can have its volume determined by comparing its mass in
water.
Is there any method or means or anything that could be used to
determine the surface area of this shape? Whether that be theoretical
mathematical formula to using a special infrared technique,etc...
The problem I foresee is that the component parts cannot be divided
into smaller geometric shapes. I would propose an answer although I
don't know if it is a good one: A liquid material that dries superthin, but
has a very specific and easily determined volume/mass is coated over
the object. Measure the mass difference between the beginning sample
of fluid and the mass after the object has been coated. Then determine
the surface area of the same mass of fluid in a geometric shape.
Is this feasible? Answered by Robert Dawson. 





An irregular, truncated pyramid 
20081024 

From phillip: Hi, I have a rectangular base to square top, pyramid shape to fabricate out
of steel plate (4 sections). The base is 3000mm by 800mm, the height is
1100mm and the top is 350mm square. What I need to know is the
lengths of the sides of the plate(were they meet vertically). Hope ive made
it clear enough. Thanks Phil. Answered by Stephen La Rocque. 





Irregular polygon and Circle that Intersects All Sides 
20080820 

From Xetro: Hi,
Suppose you have an irregular polygon(convex or concave) with n > 3 sides.
The question is  Find some circle that will cut(in limiting case  touch) all the sides of that polygon.
It doesnt matter how many times it cuts the side(1 or 2), it just have to cut or touch it.
How to find such a circle? or how to decide if such circle even exists?
What if those segments do not form a polygon but are some arbitrary segments ?
Really want to know how to do it................
Thanks a lot..
Regards,
Xetro Answered by Janice Cotcher. 





How do i find the area of an irregular figure? 
20080610 

From DAVE: How do i find the area of an irregular figure? 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. 





An irregular tetrahedron 
20080424 

From RAUL: I am looking an expression for an edge length as function of the other five edge lengths of irregular tetrahedron. Answered by Walter Whiteley. 





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. 





The centroid of a polygon 
20071229 

From David: I am playing around with an idea. I've read previous answers to questions
(using surveyor calculation methods) related to finding the area of an irregular
shape parcel of land (or irregular polygon). Is there a formula or method for
calculating the centroid (midpoint) for this type of polygon. I've seen plenty
of methods for calculating the midpoint for a triangle or regular shape poloygon
but few for an irregular shape polygon such as a parcel of land. Thanks... Answered by Harley Weston. 





An irregular octagon 
20071223 

From Sheldon: I am attempting to construct an irregular octagon picture frame out of bamboo. The bamboo is 1" in diameter and the opening should be 20" H X 16"W.
What measurements should be used? Answered by Penny Nom. 





An irregular lot 
20070912 

From Jay: How do I calculate the area of the following Lot?
N 15 degrees 1 minute 22 seconds E for 182.2 feet
S 89 degrees 46 minutes 26 seconds E for 218.4 feet
N 51 degrees 16 minutes 21 seconds E for for 307.1 feet
L= 31.63 feet with a radius of 50 feet
There is a discrepancy between county records and what the landowner is telling me Answered by Stephen la rocque and Harley Weston. 





Is there a way I can calculate correct square footage for odd shapes? 
20070831 

From Tom: I manage a golf course, and we are about to over seed the course for the upcoming winter months. We will be over seeding all greens, fairways, and tee boxes. Noone of the area that we will be placing seed on is a regular shape. The closest shapes they would be is a circle, rectangle or square, but most of them are all odd CURVED shapes. I know what the equation is for Square ft., and I know how many Square ft. are in an acre, but I need to be precise with the amount of seed I order. Is there a way I can calculate correct square footage for odd shapes. Answered by Harley Weston. 





An irregular hexagon 
20070703 

From Rebecca: I need to find the shape of an irregular hexagon, but only have the lengths four of the sides.
It actually looks like a rectangle with a trapezoid on top of it.
The bottom of the rectangle is 150'. The sides are 75'. The length of the top is 130'. I do not have the lengths
of the two smaller sides.
Is there any way to find the area of this shape? Answered by Penny Nom. 





The area of an irregular polygon 
20070627 

From chris: finding square footage of a polygon with unequal measurements Answered by Stephen La Rocque and Harley Weston. 





What is the name of the shape that is 3D and irregular? 
20070614 

From alan: What is the name of the shape that is 3D and irregular? Answered by Stephen La Rocque and Penny Nom. 





Discovering the incircle of an irregular polygon 
20070525 

From Joaquim: I've been searching in some books and many websites, but I couldn't find a formula or algorithm for discovering the incircle of an irregular polygon, could you please help me? Answered by Walter Whiteley. 





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. 





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. 





An irregular polygon 
20070306 

From Dike: How do i construct an irregular polygon Answered by Penny Nom. 





Irregular multi sided polygon 
20070120 

From Graham: I have an irregular polygon. I know the length of all the sides and know approximately all the internal angles. Is there a formula or table that can calculate the area for me? Answered by Steve La Rocque, Chris Fisher and Penny Nom. 





The area of an irregular pentagon 
20070118 

From Ranjit: I would like to find the area of an irregular pentagon where the total perimeter is 1000m. Is there a Heron's formula for this? Answered by Stephen La Rocque. 





The area of an irregular hexagon 
20061030 

From Ashish: I want to find out area of an irregular HEXAGON in square feet, whose sides are as follows, Answered by Stephen La Rocque. 





Is a circle a regular shape? 
20061010 

From David: Is a circle a regular shape or an irregular shape? Answered by Stephen La Rocque. 





The area of an irregular octagon 
20060823 

From Billy: How do you figure the area of an irregular octagon? Measurements are 4 equal sides of =BD", and 4 equal sides of =BE". It measures 1 1/2" = from flat to flat. Answered by Penny Nom. 





The area of a lot 
20060805 

From Lyn: I have no idea how to find the square feet of an uneven polygon. I am in the process of making a land agreement and need to know.
Please tell me how to figure out the footage and acreage of land as follows.
roadfront 360'
back 360'
left side 220'
right side 180' Answered by Penny Nom. 





An irregular quadrilateral 
20060204 

From Christopher: Is there such a shape as an irregular quadrilateral with 4 equal sides? Answered by Penny Nom. 





An irregular octagon 
20060120 

From Robert: I am building a poker table which is in the shape of an irregular octagon. I know the table measures 72 inches long and 48 inches wide with two parallel straight sides of equal length and six smaller sides of equal length ( three at each end of the table), what I don't know are the lengths of the any of the sides. Answered by Harley Weston. 





The area of an irregular semicircle 
20051014 

From Bob: Is there a way to compute the area of an irregular semicircle i.e. one in which the arc length is not determined by the diameter; and is therefore not technically any part circular  yet still possessing an arched side? Answered by Penny Nom. 





The area of a lot 
20040109 

From Lea:
I have a problem. I am interested in purchasing a piece of property which has the following dimensions. It is 259.10 Feet on the north side x 61.20 Feet on the east side x 217.80 Feet on the south side x 196.70 Feet on the west side. It looks like an irregular rectangle shape. How do you figure out the square footage on this irregular sized property, and what is the correct square footage answer.
I have attached a survey map. Answered by Harley Weston. 





The volume of an irregular tetrahedron 
20031124 

From Peter: How do I calculate the volume of an irregular shaped tetrahedron where: side a = 1.4 m side b = 1.4 m side c = 1.2 m and height = 0.75 m at the junction of sides a and b. Answered by Penny Nom. 





A circle around an irregular polygon 
20031103 

From Dale: How do I find the properties of a circle that is drawn around an irregular polygon of (n) sides with the lenghts of each side given and all end points of the polygon lye on the circumferance of the circle? Answered by Chris Fisher. 





The area of an odd shaped piece of property 
20030724 

From Barry: What is the formula for figuring the square footage of an odd shaped piece of property? Answered by Penny Nom. 





The area of platts 
20010220 

From Steve: I have to calculate the areas of different "platts" of land from a map, and the only thing I have are the four side measures. There are some cases where no sides are parallel, no lengths the same, and no angles are given, and I was wondering how to calculate the area of such figures. I've attached a rough sketch of a typical platt's shape. Answered by Walter Whiteley. 





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. 





Regular and irregular shapes 
19991003 

From Samuel Tighe: What is the difference between a regular shape and an irregular shape? Are a rectangle and a triangle regular or irregular shapes? Answered by Walter Whiteley. 





Area of an irregular shaped objects. 
19990407 

From Jesse Townsend: How do I find the surface area of an irregulary shaped object such as someone's knee from the thigh to shin? Thanks. Answered by Walter Whiteley. 

