







Parallel and Perpendicular lines 
20170717 

From Karen: Find an equation for the line with the given properties. Perpendicular to the line 7x + 2y = 6; containing the point (2, 1)
Find an equation for the line with the given properties. Parallel to the line 5x  3y =6; x intercept = 3 Answered by Penny Nom. 





Parallel lines 
20161026 

From Jordan: (7,5) 3x 4y=5 Answered by Penny Nom. 





A transversal 
20110330 

From Jillian: I don't understand finding angels in a transversal Answered by Penny Nom. 





Forming a square 
20091021 

From christianah: Two parallel lines have the equations y=x+4 and y=x2.Two additional lines are drawn to form a square.What is the side length of the square?Write possible equations for the additional lines.Explain and justify your reasoning. Answered by Penny Nom. 





Parallel lines 
20090701 

From chris: Write the slope of a line that is parallel to each line.
1.y=2x5
2.y=x+2
3.3x+y=10
4.5xy=11
5.x+2y=6
6.2x3y=9
7.4x+y=3
8.x+2y=14 Answered by Brennan Yaremko. 





Parallel and perpendicular lines 
20090408 

From Blake: I need to know what the formula for working a problem. I need to know how to find if i line is parallel or perpendicular by only looking at the equation. i know you must know the slope but how do i find slope? Answered by Stephen La Rocque. 





Are these lines parallel? 
20090206 

From Conor: are these lines parallel?
y = 3x 2 and 6y = 3x +2 Answered by Stephen La Rocque. 





A geometric construction 
20081017 

From M: Given any 3 parallel lines on a plane, how to construct an equilateral triangle with each vertex on each line? Answered by Chris Fisher. 





Parallel and perpendicular lines 
20080906 

From C: Can you help me determine whether these lines are parallel, perpendicular or neither and why?
Problem 1: y=3x+2
y=1/3x  4
Problem 2: y=1/3x + 1/2
y=1/3 x 2 Answered by Penny Nom. 





Proving a quadrilateral is a rectangle 
20070714 

From Sonja: I was having this discussion with another teacher and we need a third opinion. When you are trying to prove a quadrilateral is a rectangle which method should you use:
 Prove the shape is a parallelogram by doing slope 4 times by stating that parallel lines have equal slopes. Then proving a right angle by stating that perpendicular lines have negative reciprocal slopes.
 Doing the slope 4 times and stating that the shape is a rectangle because opposite sides are parallel because of equal slopes and it contains a right angle because of negative reciprocal slopes.
I guess the real question is do you have to first state that the shape is a parallelogram? Answered by Stephen La Rocque. 





The distance between parallel lines 
20070528 

From Kristie: I can't figure out how to determine the distance between parallel lines I am taking
linear algebra and vector geometry. I was given two lines in the form #x+#y =#
told they were parallel and asked to find the distance between them??
Please help
Thanks Answered by Penny Nom. 





Slicing a doublenapped cone with a plane 
20070507 

From Andrew: I am writing a paper about creating parallel lines by slicing a doublenapped cone with a plane. I have found out how it can be shown by algebra that the equations for parallel lines are generated from the degenerate case of a second degree polynomial in two variables, but I have yet to find a source with a visual representation of this case. Do you know if it exists? Answered by Chris Fisher. 





Two parallel lines 
20070425 

From prasanna: Let me know the Equation of a line which is parallel to some other line at a distance of Dmts. Answered by Penny Nom. 





A line that is perpendicular to another line 
20070316 

From Jesse: How do you write an equation of a line that is perpendicular to
y+2x+3 and passes through (3,4); I don't understand the steps
of how to do this???? Answered by Stephen La Rocque and Penny Nom. 





Prove that the triangle ABC is isosceles 
20070305 

From Lisa: I am stuck on this problem... If AB = CD (parellel line), and Answered by Stephen La Rocque and Penny Nom. 





Parallel lines 
20070227 

From Jennifer: How to you decide whether the graphs of these two equations are parallel linse: y=3x+2, y=1/3x+4 Answered by Stephen La Rocque and Penny Nom. 





An angle in a parallelogram 
20060813 

From Sam: Parallelogram ABCD has diagonal AC equal in length to side AB. CD is produced to E so that D is between E and C. If angle BAC =30 degrees find the size of angle ADE. Answered by Stephen La Rocque. 





Two parallel lines 
20060122 

From Marbara: On my math homework I have a problem where it says find the value of x so that L is parallel to M
on one of the there are three lines. the top one is horizontal which is L. the bottom one is also horizontal directly under L which is M. there is another line that is diagonal going through the middle sections of L and M.
To the right of the diagonal line and right under line L is an equation 5x10
to the right of the diagonal line and right above line M is an equation 8X5
I tried to find what X is but I can't because it never matches both equations no matter what way I try to do it. Answered by Penny Nom. 





What is the angle between 2 noncollinear parallel lines? 
20051017 

From Ben: What is the angle (if any) between 2 noncollinear parallel lines? Answered by Chris Fisher and Walter Whiteley. 





A theorem involving a trapezoid 
20040929 

From Abraham: Given:Trapezoid ROSE with diagonals RS and EO intersecting at point M
Prove:Diagonals RS and EO do not bisect each other. Answered by Harley Weston. 





Parallel and perpendicular lines 
20000508 

From Jimmy Lumpkins: Need a method for solving the following problem: Find the equation of a line through point P that is parallel or perpendicular to another line. Answered by Paul Betts. 





Parallel lines 
20000112 

From Lori: Find an equation of the line parallel to the given line containing the given point. x + y = 2; (1,2) We know parallel line have the same slope and we know the answer y = x + 3. Answered by Penny Nom. 





Prove that these two lines are parallel. 
19960529 

From Adam Piekarzewski: Using parallel line theorems and side angle side etc. in triangle acd a line is drawn from point b on ac and point i on ad. another triangle fliped vertically and joined at d is named fdh, a line is drawn from point e on fd and point g on fh. ab = fg, ai = fe, ac  fh prove that bi  eg / / Answered by Harley Weston. 

