Question

3) Resolver as seguintes equações ( na incógnita x):

a) 5/x-2=1/4 (X≠0)

b) 3x+6=7x+3x

Answer 1

a)

$\frac{5}{x} -2 = \frac{1}{4} \\ \\ \frac{5-2x}{x} = \frac{1}{4} \\ \\ x = 4(5-2x)\\ \\ x = 20-8x\\ \\ x+8x = 20 \\ \\ 9x = 20 \\ \\ x = \frac{20}{9}$

b)
$3x+6=7x+3x \\ \\ 3x + 6 = 10x \\ \\ 3x - 10x = -6 \\ \\ -7x = -6 .(-1) \\ \\ 7x = 6 \\ \\ x = \frac{6}{7}$