Cos(5x)cos(2x) - sin(5x)sin(2x)

What are the coordinates of the midpoint of ab? ,1/2) /2,-1) ,-3/2) /2,-2)

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

What is the anwers for 9+2x=5x-3-x