Question

4(×+5)+3(×+5)=21...​

Answer 1

Resposta:

$4(x + 5) + 3(x + 5) = 21 \\ 4x + 20 + 3x + 15 = 21 \\ 7x + 35 = 21 \\ 7x = 21 - 35 \\ 7x = - 14 \\ x = - 14 \div 7 \\ x = - 2$

Answer 2

Resposta:

$4(x + 5) + 3(x + 5) = 21 \\ 4x + 20 + 3x + 15 = 21 \\ 4x + 3x = 21 - 20 - 15 \\ 7x = -14 \\ x = \frac{-14}{7} \\ x = -2$