Question

12x+3(4x-5)=2x+7x-5x

Answer 1

X= 3/4, se tiver dúvida em alguma parte, me fale

Answer 2

$12x + 12x - 15 = 2x + 7x - 5x \\ 12x + 12x - 2x - 7x - 5x - 15 = 0 \\ 10x - 15 = 0 \\ 10x = 15 \\ x = \frac{15}{10}$