Question

4) Resolva as equações: a) x – 3.(4 – x) = 7x – (1 – x) S = b) 3.(x + 2) = 2.(x – 7) S = c) 2.(x – 1) + 3.(x + 1) = 4.(x + 2) S = d) 3.(x + 1) + 2 = 5 + 2.(x – 1) S = e) 16x + 2.(7x + 8) – 9 = 67 S = f) 13.(2x – 3) – 5.(2 – x) = 5.(-3 + 6x) S =

Answer 1

Oie, Td Bom?!

a)

x - 3 . (4 - x) = 7x - (1 - x)

x - 12 + 3x = 7x - 1 + x

- 12 + 3x = 7x - 1

3x - 7x = - 1 + 12

- 4x = 11

x = 11/-4

x = - 11/4 ⇒ S = {- 11/4}

b)

3(x + 2) = 2(x - 7)

3x + 6 = 2x - 14

3x - 2x = - 14 - 6

x = - 20 ⇒ S = {- 20}

c)

2(x - 1) + 3(x + 1) = 4(x + 2)

2x - 2 + 3x + 3 = 4x + 8

5x + 1 = 4x + 8

5x - 4x = 8 - 1

x = 7 ⇒ S = {7}

d)

3(x + 1) + 2 = 5 + 2(x - 1)

3x + 3 + 2 = 5 + 2x - 2

3x + 5 = 3 + 2x

3x - 2x = 3 - 5

x = - 2 ⇒ S = {- 2}

e)

16x + 2(7x + 8) - 9 = 67

16x + 14x + 16 - 9 = 67

30x + 7 = 67

30x = 67 - 7

30x = 60

x = 60/30

x = 2 ⇒ S = {2}

f)

13(2x - 3) - 5(2 - x)= 5(- 3 + 6x)

26x - 39 - 10 + 5x = - 15 + 30x

31x - 49 = - 15 + 30x

31x - 30x = - 15 + 49

x = 34 ⇒ S = {34}

Att. Makaveli1996