Question

Resolva as equações :
a) 3/5-7=x+10
b) 4x-1=x/4+1/2
c) -x+2/2=8x+10/4

Answer 1

a) $\frac{3}{5}$ - 7 = x + 10
$\frac{3}{5}$ - 7 - 10 = x
$\frac{3}{5}$ - 17 = x
$\frac{(5.(-17))+3}{5}$ = x
$\frac{-85+3}{5}$ = x
$\frac{-82}{5}$ = x

b) 4x - 1 = $\frac{x}{4}$ + $\frac{1}{2}$
4x - $\frac{x}{4}$ = $\frac{1}{2}$ + 1
$\frac{(4.4x)+x}{4}$ = $\frac{(2.1)+1}{2}$
$\frac{16x + x}{4}$ = $\frac{2+1}{2}$
$\frac{16x + x}{4}$ = $\frac{3}{2}$
(16x + x) × 2 = 4 × 3
32x + 2x = 12
32x = 12
x = $\frac{12}{32}$
x = $\frac{6}{16}$
x = $\frac{3}{8}$

c) $\frac{-x+2}{2}$ = $\frac{8x + 10}{4}$
(- x + 2) × 4 = 2 × (8x + 10)
- 4x + 8 = 16x + 20
- 4x - 16x = 20 - 8
- 20x = 12
x = - $\frac{12}{20}$
x = - $\frac{3}{5}$