Question

resolva as equações abaixo: a) 5x+21=10x-19
b) 4(x+5)=40
c)4x-30=90

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Answer 1

a) 5x + 21 = 10x - 19

5x - 10x = -19 - 21

-5x = -40 ×(-1)

5x = 40

x = 40/5

x = 8

b) 4 (x + 5) = 40

4x + 20 = 40

4x = 40 - 20

4x = 20

x = 20/4

x = 5

c) 4x - 30 = 90

4x = 90 + 30

4x = 120

x = 120/4

x = 30