Question

(2a-5)^2-(2a+3)^2=-80

Answer 1

(2a-5)^2 - (2a+3)^2=-80
(2a-5-2a-3)(2a-5+2a+3)=-80
-8(4a-2)=-80
4a-2= 10
4a=10+2
4a=12
a=3

Answer 2

(2а - 5)^2-(2а+3)^2=-80; 4а^2-20а+25-4а^2-12а-9=-80: 32а+16=-80; 32а=-96; а=-3;