Respostas

  • Usuário do Brainly
2014-03-21T11:11:52-03:00
A.
(3y+4)²
9y+16
9²+2.9.16+(16)²
81+288+256=625

B.
(6a-3):(6a+3)
6²-2.6.3+(3)² : 6²+2.6.3+(3)²
36-36+9 : 36+36+9
36-36-36-36+9-9=-72

C.
(y-4)²
1²-2.1.4+(4)²
1-8+16
-7+16=9