Question

a){2x+2y=30
{2x-2y=2

b){y=3x
{-5x+2y=2

Answer 1

Resposta:

A)  x=8 e y =7

b) x = 2 e y=6

Explicação passo-a-passo:

a)

$\left \{ {{2x+2y=30} \atop {2x-2y=2}} \right. \\\\4x= 32\\x= \frac{32}{4} \\x= 8\\\\2x+2y=30\\2.8+2y = 30\\16 + 2y = 30\\2y=30-16\\2y=14\\y=7$

b)

$\left \{ {{y=3x \atop {-5x+2y=2}} \right. \\\\\\-5x+2(3x) = 2\\-5x+6x=2\\x=2\\\\y=3x\\y=3(2)\\y=6$