SOLUTION: Can two intersecting lines have the same slope?

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Question 710449: Can two intersecting lines have the same slope?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
No.
If two lines have the same slope they are parallel lines (or they are the same line), so they cannot intersect at one point.
The drawing below shows why it makes sense that lines with the same slope are parallel.
The green and blue lines have slope = m.
I made right triangles by drawing a perpendicular to the x-axis(parallel to the y-axis) at a point 1 unit to the right of where each line intersects the x-axis.
because the slope of each line is m, the sides perpendicular to the x-axis have length m.
Both right triangles have legs measuring 1 and m, so they are congruent.
(It's like the same triangle sliding along the x-axis).
Because the triangles are congruent, the angles where the lines meet the x-axis are congruent.
Because the lines form the same angle with the x-axis, they are parallel.
Because they are parallel, they do not intersect