Question

3a^2- b^2 ( para a = -2 e b = - 7)

Answer 1

$3a^2-b^2~~~para~~a=-2~~e~~ b=-7\\ \\ 3(-2)^2-(-7)^2=\\ \\ 3(+4)-(+49)=\\ \\ 12-49=-37$

Answer 2

Oie, Td Bom?!

$3a {}^{2} - b {}^{2}$

Sabendo que: a = - 2 e b = - 7.

$3 \times ( - 2) {}^{2} - ( -7) {}^{2}$

$3 \times 2 {}^{2} - 49$

$3 \times 4 - 49$

$12 - 49$

$- 37$

Att. Makaveli1996