Question

Observe o exemplo e resolva as equações ​

Answer 1

Resposta:

a) x + 9=18 ⇔ x=18-9 ⇔ x=9

b)x-1=-8 ⇔ x=-8+1 ⇔ x=-7

c)3y-8=13 ⇔ 3y=13+8 ⇔ 3y=21 ⇔ y=21/3 ⇔ 7

d)12x-10=5x+11 ⇔ 12x-5x=11+10 ⇔ 7x=21 ⇔ x=21/7 ⇔ x=3

e)7x+5=68-2x ⇔ 7x+2x=68-5 ⇔ 9x=63 ⇔ x=63/9 ⇔ x=7

f)14-3x=2x+29 ⇔ -3x-2x=29-14 ⇔ -5x=15 ⇔ x=15/(-5) ⇔ x=-3

g)8x-9=2x+11 ⇔ 8x-2x=11+9 ⇔ 6x=20 ⇔ x=20/6 ⇔ x=3,(3)

h)10-4x=9-2x ⇔ -4x+2x=9-10 ⇔ -2x=-1 ⇔ x=-1/(-2) ⇔ x=1/2

i)2·(7x+2)+12·(x+1)=2 ⇔ 14x+4+12x+12=2 ⇔ 26x=2-12-4 ⇔ 26x=-14 ⇔  

x=-14/26 ⇔ x=-7/13