Question

Resolva as equações sendo U=Q a)2x+18=5 b) x+7=4x c)7x+13=2x+23 d)2m-5=14-3m e)-2x-1=5x+20 f)5-[2x-3(1-2x)]=3x-13 g)2x-3(4-x)=5+4(2x+1) h)29+1(3x-8)-2(x+6=x-9

Answer 1

a)2x+18=5
2x=5-18
2x=-13
x=-13/2

b) x+7=4x
x-4x=7
(-)-3x=7
3x=7
x=7/3

c)7x+13=2x+23
7x-2x=23-13
5x=10
x=10/5
x=2

d)2m-5=14-3m
2m+3m=14+5
5m=19
m=19/5

e)-2x-1=5x+20
-2x-5x=20+1
(-)-7x=21
7x=-21
x=-21/7
x=-3

f)5-[2x-3(1-2x)]=3x-13
5-[2x-3+6x]=3x-13
5-[8x-3]=3x-13
-45x-15=3x-13
-45x-3x=-13+15
(-)-48x=2
48x=-2
x=-2/48--> divide -2/2 e 48/2
x=-1/24

g)2x-3(4-x)=5+4(2x+1)
2x-12+3x=5+6x+4
2x+3x-6x=5+4+12
9x=21
x=21/9---> divide 21/3 e 9/3
x=7/3

h)29+1(3x-8)-2(x+6)=x-9
29+3x-8-2x-12=x-9
3x-2x-x=-9-29+8+12
3x-3x=-20+20
0=0