Respostas

2014-08-10T16:53:36-03:00
a) 1-3(4x+7)=2(x-10)
1-12x-21=2x-20
-12x-2x= -20-1+21
-12x-2x= -21+21
-14x=0 (-1)
14x=0
x=0/14 (ZERO QUATORZE AVOS)
x=0

b)3(-1-5x) - (-7x+6)= -4(x-3)
-3-15x+7x-6=-4x+12
-15x+4x+7x=12+3+6
-15x+11x=15+6
-4x=21 (-1)
4x= -21
x= -21/4 (VINTE E UM QUARTOS) OU -5,25


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