Question

considerado que as expressões 3.(1,2x-2,4) e (1+1,5)+2,8 são iguais,determine x.

Answer 1

3.(1,2x - 2,4) = (1+1,5)+28
3,6x - 7,2 = 2,5 + 28
3,6x = 2,5 + 28 + 7,2
3,6x = 28 + 9,7
3,6x = 37,7
x = 37,7/3,6
x = 377/36

Answer 2

Olá Gisel

(1 + 1.5) + 2.8 = 2.5 + 2.8 = 5.3

3*(1.2x - 2.4) = 3.6x - 7.2

3.6x - 7.2 = 5.3

3.6x = 5.3 + 7.2 = 12.5 

x = 12.5/3.6 = 3.47222...

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