Question

Resolva as equações de 1 grau:
2x+7=18

B:10x-9=21+2x+3x

C:3x-2x+10=10+5-40

D:10-(8x-2)=5x+2(-4x+1)

E:10x-5(1+x=3(2x-2)-20

Answer 1

a)2x+7=18
2x=18-7
2x=11
x=11÷2
x=5,5

b)10x-9=21+2x+3x
10x-9=21+5x
10x-5x=21+9
5x=30
x=30÷5
x=6

c)3x-2x+10=10+5-40
3x-2x=10+5-40-10
1x=15-50
1x=-35

d)10-(8x-2)=5x+2(4x+1)
10-8x+2=5x+8x+2
-8x-5x-8x=2-2-10
-21x=-10
x=-10÷-21
x=10÷21

e)10x-5(1+x)=3(2x-2)-20
10x-5-5x=6x-6-20
10x-5x-5=6x-6-20
5x-5=6x-26
5x-6x=-26+5
-1x=-21
x=(-21)÷(-1)
x=21