Question

a) 3•(x+8)=60
b) 5•(x-1)=x+40
c) 3•x-2,4=15-x
d) 9•x-5,8=x-19
e) 3•(2•x+4)=39-2•(x+5)
f) 5•(x+3)=x+7,6

Answer 1

Explicação passo-a-passo:

$a) 3.(x+8)=60 \\ x + 8 = 20 \\ x = 20 - 8 \\ x = 12$

$b) 5.(x-1)=x+40 \\ 5x - 5 = x + 40 \\ 5x - x = 40 + 5 \\ 4x = 40 + 5 \\ 4x = 45 \\ x = \frac{45}{4}$

$c) 3.x-2,4=15-x \\ 3x-2,4=15-x \\ 3x + x = 15 + 2,4 \\ 4x = 15 + 2,4 \\ 4x = 17,4 \\ x = \frac{17,4}{4} \\ x = 4,35$

$d) 9.x-5,8=x-19 \\ 9x-5,8=x-19 \\ 9x - x = - 19 + 5,8 \\ 8x = - 19 + 5,8 \\ 8x = - 13,2 \\ x = \frac{13,2}{8}$

x=- 1,65

$e) 3.(2.x+4)=39-2.(x+5) \\ 3.(2x + 4)=39-2.(x+5) \\ 6x + 12 = 39 - 2x + 10 \\ 6x + 12 = 29 - 2x \\ 6x + 2x = 29 - 12 \\ 8x = 29 - 12 \\ 8x = 17 \\ x = \frac{17}{8}$

$f) 5.(x+3)=x+7,6 \\ 5x + 15 = x + 7,6 \\ 5x - x = + 7,6 - 15 \\ 4x = + 7,6 - 15 \\ 4x = - 7,4 \\ x = \frac{ - 7,4}{4} \\ x = - 1,85$

Espero ter ajudado! <3