Question 849458
Apply FOIL on the left side.

(a+1)(a+1) = 25

a^2+2a+1 = 25

a^2+2a+1 - 25 = 0

a^2+2a-24 = 0

(a-4)(a+6) = 0


Set each factor to equal zero and solve for a.

a-4 = 0

a = 4


Now the next factor.

a+6 = 0

a = -6


Answer: a = 4 and a = -6.