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Question

misty1212 · Answer

HI!!

misty1212 · Answer

the slopes of both lines are zero
calculate the slope, you will get zero for both

undeadknight26 · Answer

What the awesome white girl said :D

leahhhmorgannn · Answer

I figured that proving the slope was the same would be a right answer, but I'm not sure how to find the slope with the given values? 
Like I know the formula and it's usually pretty easy, but the points that are given are confusing to plug into that formula?

misty1212 · Answer

which is another way of saying that the y coordinates are the same for both lines

misty1212 · Answer

just look at the  y's
the first one  is $(0,0)$ and $(x_2,0)$ 
the y coordinates are the same, (both zero) so the slope is zero

leahhhmorgannn · Answer

so that proves AB, but how does that prove that DE is parallel to AB?

misty1212 · Answer

for the second one, both y coordinates are $\frac{y_1}{2}$

misty1212 · Answer

that proves that the slope of AB is 0

misty1212 · Answer

now to prove DE has slope 0, say that the y coordinates of both points are the same
that means the slope is 0

misty1212 · Answer

then since both AB and DE have the same slope (both zero) they must be parallel

leahhhmorgannn · Answer

Ohh, I think I see now. 
Both D and E have the y coordinates of y1 over 2, right? So they have the same slope.

misty1212 · Answer

lets go slow an make sure it is clear

misty1212 · Answer

'Both D and E have the y coordinates of y1 over 2, right? "
yes that means the slope of DE is zero

misty1212 · Answer

and since the slope of AB is zero, the lines are parallel

leahhhmorgannn · Answer

Okay, that clarifies the question a lot for me.

misty1212 · Answer

ok good!

leahhhmorgannn · Answer

Thank you so much

misty1212 · Answer

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