Question

Sabendo que r//s, determine x.

Answer 1

A)
$3x-12=2x+15$
$3x-2x=15+12$
$x=27$

B)

$3x=x+40$
$3x-x=40$
$2x=40$
$x=20$

C)

$3x+20+2x-30=180$
$5x-10=180$
$5x=180+10$
$5x=190$
$x= \frac{190}{5}$
$x=38$