Question

Calcule ( A+3) × ( A-3)=​

Answer 1

* = elevado ao quadrado

(A+3) ×(A-3) =

A*2 -3A +3A -9 =

A*2 -9

resposta : A*2- 9

Answer 2

Vamos lá,

(a + 3) × (a − 3)

(a + 3)(a + −3)

(a)(a) + (a)(−3) + (3)(a) + (3)(−3)

a^2 − 3a + 3a − 9

a^2−9