Question

Resolva as equações do 1º grau abaixo:

a) x + 5 = 8

b) x + 9 = -1

c) 2x + 4 = 16

d) 33 + x = 5 – 3x

e) 7x – 33 = - 12

f) 9x – 2 = 4x + 18

g) 4x – 18 + 3x = 10

h) 7x + 1 = 5x – 7

i) 2(x + 5) -4 = 26

j) 3(x + 2) = 2(x - 7)

k) 3(2x - 3) + x = 5

l) 3(x + 1) + 2(2x - 3) = 5(x - 1) + 8

Answer 1

Resposta:

a)

$x + 5 = 8 \\ x = 8 - 5 \\ x = 3$

b)

$x + 9 = - 1 \\ x = - 1 - 9 \\ x = - 10$

c)

$2x + 4 = 16 \\ 2x = 16 - 4 \\ 2x = 12 \\ x = \frac{12}{2} \\ x = 6$

d)

$33 + x = 5 - 3x \\ x + 3x = 5 - 33 \\ 4x = - 28 \\ x = \frac{ - 28}{4} \\ x = - 7$

$h \\ 7x + 1 = 5x - 7 \\ 7x - 5x = - 7 - 1 \\ 2x = - 8 \\ x = \frac{ - 8}{2} \\ x = - 4$

e)

$7x - 33 = - 12 \\ 7x = - 12 + 33 \\ 7x = 21 \\ x = \frac{21}{7} \\ x = 3$

f)

$9x - 2 = 4x + 18 \\ 9x - 4x =18 + 2 \\ 5x = 20 \\ x = \frac{20}{5} \\ x = 4$

g)

$4x - 18 + 3x = 10 \\ 4x + 3x = 10 + 18 \\ 7x = 28 \\ x = \frac{28}{7} \\ x = 4$

i)

$2(x + 5) - 4 = 26 \\ 2 \times x5 - 4 = 26 \\ 10x - 4 = 26 \\ 10x = 26 + 4 \\ 10x = 30 \\ x = \frac{30}{10} \\ x = 3$

j)

$3(x + 2) = 2(x - 7) \\ 3 \times 2x = 2 \times ( - 7x) \\ 5x = - 14x \\ 5x - 14x = 0 \\ - 9x = 0 \: \: \: \: \: \: ( - 1) \\ 9x = 0 \\ x = 9$

k

$3(2 \times - 3) + x = 5 \\ 3 \times( - 1x) + x = 5 \\ - 2x = 5 \\ x = \frac{5}{2}$

L)

$3( x + 1) + 2(2x - 3) = 5(x - 1) + 8 \\ 3 \times 1x + 2 \times ( - 1x) = 5 \times ( - 1x) \\ 3x + ( - 2x) = - 5x + 8 \\ 3x+ ( - 2x) + 5x = 8 \\ 6x = 8 \\ x = \frac{8}{6}$

Explicação passo-a-passo:

Espero ter ajudado!!!