Question

Best answer with explaination gets a medal
The coordinates of quadrilateral PQRS are P(0, 0), Q(a + c, 0), R(2a + c, b), and S(a, b). How can you use coordinate geometry to show that one pair of opposite sides is parallel?

A. Find the slopes of PR andQS, and show that their product are equal.
B. Find the slopes of PQ and RS, and show that they are equal.
C. Find the slopes of PQ and RS, and show that their product is 1.
D. Find the slopes of PR and QS, and show that their product is -1.

Answer 1

there are a number of ways, one would be using some linear algebra, another could be, finding the equation of the lines and comparing their slope.

Answer 2

Hmm, Okay. how do you mean?

Answer 3

We would take a pair of points, find their slope and line equation.
Then we would the the other two, and apply the same process.
if we'd compare both equations we would find that their slope are the same wich means that the opposite side is parallel to the other.

Answer 4

Okay thanks! :)

Answer 5

at your service ;)