Question

ajuda ae !!!! Produtos Notaveis

Answer 1

Explicação passo-a-passo:

$a)\;(x+3)\cdot(x-3)+(x+7)^2\\\\x^2-3^2+x^2+14x+49\\\\2x^2-9+14x+49\\\\2x^2+14x+40$

$b)\;(y-5)^2-(y+4)^2\\\\y^2-10y+25-(y^2+8y+16)\\\\y^2-10y+25-y^2-8y-16\\\\-18y+9$