What is the length of DE

A. 7

B. 6

C. 5

D. 8

In the following diagram it is given that dec,ab || dc, ad || eb, and ad is congruent to bc. a)why isn't abc a parallelogram even though it has a pair of parallel sides and a pair of congruent sides b)explain why be must be congruent to bc. further explain what type of triangle this makes triangle abc and what it tells you about angle 1 and angle 2c) finally why must angle 3 be congruent to angle 1? further, explain why we know that angle 3 is congruent to angle 2

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

Cole says the distance between points (-5,0) and (0,-5)is 5 units. is he correct? explain why or why not.