31 items are filed under this topic.
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An analytic proof that a quadrilateral is a parallelogram |
2020-10-26 |
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From Apollo:
Prove analytically that if ABCD is a parallelogram in which points P and Q trisects the diagonal AC, then BPDQ is a parallelogram.
Answered by Penny Nom. |
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A confusing problem |
2020-10-01 |
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From Kgaugelo:
a triangle has the vertices A(-4;-3),B(x;y)and C(2;1). Determine the coordinates of B if the equation of the line BC is y=5x-9
Answered by Harley Weston. |
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Points on the x-axis |
2015-03-14 |
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From Justin:
jamie tells her friend that ordered pairs that have an x-coordinate of O line x-axis. She used the origin as an example. Describe Janine error. Use a counterexample to explain why Janine statement is false
Answered by Penny Nom. |
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A region described by inequalities in cylindrical coordinates |
2015-02-21 |
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From Rahul:
I am not able to visualize a solid given by inequalities as under (in cylindrical coordinate system)
0=
I know that (can visualize) first 2 inequalities say it is a cylinder of infinite length.
It seems that third inequality poses the restriction to the height as well as it makes us to remove a cone.
But I just can not understand it clearly.
Thanks in advance!
Regards,
Rahul
Answered by Penny Nom. |
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Equal ordinate and abscissa |
2013-08-15 |
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From sonit:
the slope of tangent to the curve y=(4-x^2)^1/2 at the point, where the ordinate and abscissa are equal, is
Answered by Penny Nom. |
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r=10cos(t) in cylindrical coordinates |
2013-05-18 |
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From r.m:
question from calculus exam: what is the figure obtained having eqn.r=10cos(t) in cylinderical coordinates?
i know it is a cylinder with center (5,0) ,but can't the equation represent two cylinders ,one with center
(5,0) and the other with center (-5,0).
thanks for any help.
Answered by Penny Nom. |
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Polar coordinates |
2010-04-14 |
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From Lan:
Given the rectangular equation (x^2)+2x+(y^2)+y=0, find the polar equation.
Answered by Harley Weston. |
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Integration of cos (x^2+y^2) dx dy |
2010-02-12 |
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From anna:
How do you evaluate the integration of integration of cos (x^2+y^2) dx dy?
Answered by Tyler Wood. |
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The line through D(-4, 0) and E(2, 6) |
2009-11-16 |
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From Rogerson:
The point F is on the line through D(-4, 0) and E(2, 6) so that DF=4DE. Find the coordinates of F.
Answered by Penny Nom. |
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A side of a rectangle |
2009-07-15 |
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From hanbal:
Could please help solving this problem
A(1,3) and D(5,5) are two vertices of a rectangle ABCD. The equation of line AC is 3y=4x + 5
Find
a) the equation of line DC
Answered by Chris Fisher. |
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Subdividing a four-sided lot |
2009-03-27 |
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From kannan:
i have a 1.5 acre land having four sides
A-B=64.8 meters
B-C=94.2 meters
C-D=54.4 meters
D-A=127.2 meters
angle at D is 90
the side AB (frontage)is road facing i want to split the plot in to two halves
having same almost area and almost equal frontage, kindly help me, if possible
explain with drawing.
Regards
Kannan
Answered by Harley Weston. |
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Cutting a pipe at an arbitrary angle |
2008-09-20 |
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From John:
from the original question Al asked about cutting a 200 diameter pipe in 45 degrees. can someone explain the math steps required to creating the graph. I am trying to do the same thing only using a 150 degree cut.
Answered by Harley Weston. |
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Vectors and an orientation change in the axes |
2008-08-30 |
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From moumita:
what differences take place to a vector because of choice of orientation of the coordinate axes and why??
Answered by Harley Weston. |
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A regular hexagon |
2008-05-20 |
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From Martin:
Given a regular hexagon with center on the origin of an x-y plane with coordinate (r,0) on the x axis, we are to express the coordinates of "A" located at 120 deg from (r,0) in terms of "r".
Answered by Janice Cotcher. |
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Three points on the circumference of a circle |
2007-07-30 |
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From Bharathi:
given a circle with radius r and a point x,y on its circumference,output two other
points x1,y1 and x2,y2 on the circle so thar all 3 points form a equilateral triangle.
Answered by Stephen La Rocque. |
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What is the equation? |
2006-09-13 |
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From A parent:
HERE ARE THE COORDINATED (0,-3), (1,0), (2,3),(3,6)
WHAT IS THE EQUATION?
Answered by Penny Nom. |
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Plotting co-ordinates on a number plane |
2006-09-08 |
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From Victor:
I need to plot co-ordinates (0,2), (2,-2), (-2,0), and (0,0) on a number or co-ordinates plane, I am not sure how to do this, and get lost after the first point, can you please help?
Answered by Penny Nom. |
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Polar to Cartesian coordinates |
2006-01-15 |
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From Linden:
How do you convert six units at 30 degrees Polar Coordinate into a Cartesian Coordinate?
Answered by Penny Nom. |
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Converting coordinates |
2004-10-25 |
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From Allen:
I am trying to help my son with his home, but I don't remember these conversions. Please help.
1. Convert the following coordinates
Cartesian x = 7, y = -24
2. Convert the following coordinates
Polar r = 4, theta = pi / 3
Answered by Penny Nom. |
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Terminology |
2003-08-31 |
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From Maria:
My daughter Veronica is a rising 6th grader and has to complete some Summer Math
assignments and would like to ask you three questions:
- ___________ are number pairs that have a product of 1.
- You can name any point on a plane with two numbers. These two numbers are called _____________.
- A _______________ is the size of a cube that is exactly 1 inch on each edge.
Thanks,
Answered by Penny Nom. |
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A triangle in the complex plane |
2003-07-10 |
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From Scott:
The vertices O and A of an EQUILATERAL triangle OAB in the complex plane are located at the origin and 3 + 3i. Find all possible values for the complex number representing the vertex B. Give the location of B in both polar and cartesian form (to 2.d.p)
Answered by Penny Nom. |
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Transformations of pattern blocks |
2003-02-06 |
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From Cheryl:
I am trying to help my 8th grade son with Transformations - use of patttern blocks. He has to trace a figure and reflect it across the x-axis, which I can do, but then it indicates include ordered pairs - that confuses me.
Answered by Penny Nom. |
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Counterclockwise |
2001-09-14 |
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From Rolanda:
When Descartes invented the coordinate system he decided to number them counter-clockwise. Why?
Answered by Chris Fisher. |
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Polar coordinates |
2000-02-24 |
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From Tran Trung:
How do I convert r = 2/(2sin(theta) - 3cos(theta)) to rectangular and x2 + y2 -2y = 0 to polar form?
Answered by Harley Weston. |
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A valentines project |
2000-02-21 |
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From Courtney Dohoney:
I was assigned a valentines project. Our job is to make a valentines card that has a math theme. On my valentines card I would like to include the set of equations that when graphed look like a heart. If you can figure out a set of equations and get it back to me I would be very happy.
Answered by Harley Weston. |
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A Polar Plot |
1999-05-06 |
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From Irene:
Consider the polar equation r=2-3Cos(theta/2) In the interval [o, 4Pi], how would you find the area of one of the leaves and also the length of one of the edges of a leaf?
Answered by Harley Weston. |
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Complex numbers/polar coordinates |
1999-03-25 |
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From Kate Cegelis:
What is the relationship between complex numbers and polar coordinates?
Answered by Harley Weston. |
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Intersection of planes |
1998-11-22 |
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From Dave Rasmussen:
I am a teacher of secondary mathematics with a question about the uses of Three Dimensional Co-ordinate Geometry. I have been teaching my students to write equations of planes and lines, - to find the intersection of these and the distance between them. What I am having difficulty finding are good applications of these techniques to "real world" situations. Can anybody help me?
Answered by Walter Whiteley and Harley Weston. |
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Calculating the Intersection Point. |
1997-12-10 |
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From Milton Parsons:
Given 2 lines through (x1,y1),(x2,y2),and (x3,y3),(x4,y4). Can you give me a good formula for calculating the intersection point. I would greatly appreciate it.Thanks.
Answered by Chris Fisher and Penny Nom. |
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A Geometry Problem |
1997-09-18 |
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From Rebecca Henry:
A circle is centered at the vertex of the right angle of an isosceles triangle. The cirlce passes through both trisection points of the hypotenuse of the triangle. If the length of a radius of the circle is 10, find the area of the triangle.
Answered by Chris Fisher Harley Weston. |
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Y-axis |
1997-05-29 |
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From Leah:
I know that the proper name for the X axis is the abscissa, but, what is the proper name for the Y axis?
Answered by Chris Fisher. |
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