Can some help me understand what they want me to do?

Verify that parallelogram abcd with vertices a(-5 -1) b(-9,6) c(-1,5) and d(3,-2) is a rhombus by showing that is a parallelogram with perpendicular diagonals.

Question

Can some help me understand what they want me to do?

Verify that parallelogram abcd with vertices a(-5 -1) b(-9,6) c(-1,5) and d(3,-2) is a rhombus by showing that is a parallelogram with perpendicular diagonals.

anonymous · Answer

@SolomonZelman

anonymous · Answer

@aaronq 
Do I just use distance formula from A to C and then from B to D?

anonymous · Answer

for abcd, ac and bd are diagonals, right? find ac, bd and you will see their slopes are $\perp$ 
That is , if slope of ac is $m_1$, then slope of bd is $-\dfrac{1}{m_1}$

anonymous · Answer

Oh duh thanks!