The perimeter of equilateral triangle TRY is 9y+45 and TY = 2y+25 . find the perimeter of triagle TRY.

The perimeter of a parallelogram ABCD is 66 cm, and DC is twice as long as BC . how long is AB ?

2 QUESTIONS .. ANSWERS PLEASE TELL ME WHAT TO DO

3 answers

Obviously the sides must be equal, so
9y + 45 = 2y + 25
Solve for y, sub back into the expression for the side to get its length.

2nd:
let the short side be x
then the longer side is 2x

solve:

x + x + 2x + 2x = 66
is number 1. = 7y=20 ? ?? i don't know help me on math please/
no

9y + 45 = 2y + 25
7y = -20
y = -20/7

so each side is 2y+25 = 2(-20/7) + 25
= 135/7

perimeter = 3(135/7) = 405/7 or appr 57.86