Question

Resolva as equações em R
a) 2x - x + 5 = 18

b) 3(x -2) = - 5(4 - 2x)

c) 3x/2 - 4/5 = - x/3 + 7/3

d) 5 + x-3/4 = x + 3x-1/2

Answer 1

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

b) 3(x-2)=-5(4-2x)
3x-6=-20+10x
3x-10x=-20+6
-7x=-14(-1)
7x=14
x=14/7
x=2

c)3x/2-4/5=-x/3+7/3
3x/2+x/3=7/3+4/5
(9+2)x/6=(35+12)/15
11x/6=47/15
x=47/15/11/6
x=47/15*6/11
x=282/165=94/55

d)5+x-3/4=x+3x-1/2
x-x-3x=-5+3/4-1/2
-3x=5+(6-4)/4
-3x=5+2/4
-3x=(20+2)/4
-3x=22/4(-1)
3x=-22/4
x=-22/4/3
x=22/4*1/3
x=22/12=11/6