Question

1 - (1,0) Resolva as equações abaixo, considere U=R. a) x - 3 = 9 b) 4x - 9 = 1 - 2x c) x + 5 = 20 - 4x d) 9x - 4x + 10 = 7x – 30

Answer 1

a) x - 3 = 9

x = 9 + 3

x = 12

b) 4x - 9 = 1 - 2x

4x + 2x = 1 + 9

6x = 10

x = 10 (÷2)

----

6 (÷2)

x = 5

---

3

c) x + 5 = 20 - 4x

x + 4x = 20 - 5

5x = 25

x = 25

-----

5

x = 5

d) 9x - 4x + 10 = 7x - 30

9x - 4x - 7x = - 30 - 10

- 2x = - 40 . (-1)

2x = 40

x = 40

-----

2

x = 20

Answer 2

Explicação passo-a-passo:

x - 3 = 9

x=9+3

x=12

4x - 9 = 1 - 2x

4x+2x=1+9

6x=10

x=10÷2/6÷2

x=5/3

x + 5 = 20 - 4x

x+4x=20-5

5x=15

x=15/5

x=3

9x - 4x + 10 = 7x – 30

5x+10=7x-30

5x-7x=-30-10

-2x=-40(-1)

2x=40

x=40/2

x=20