Question

my teacher gave me the answer but I do not understand, can someone explain to me how the answer is 282? (for test)

Answer 1

3(7)(x) = 252

21x = 252, so x = 12 feet

S = 2(3(12) + 3(7) + 7(12))

= 2(36 + 21 + 84) = 2(141)

= 282 square feet