Question

O valor de x na equação 40x = 12x + 4 é: *

A) 1/7
B) 1/5
C) 2/3
D) 6/7

5) O valor de x na equação 3x + 10 – x = 5x – 1 + 2x é: *

A) 11/5
B) 3/7
C) 4/7
D) 7/23

Answer 1

$40x = 12x + 4$

$4 = 40x - 12x$

$28x = 4$

$x = \frac{1}{7}$

$3x + 10 - x = 5x - 1 + 2x$

$2x + 10 = 7x - 1$

$2x - 7x = - 5x = - 1 - 10$

$- 5x = - 11$

$x = \frac{11}{5}$