Question

9. Resolva as seguintes equações:
Ha)x+3=7
b) 2t - 5 = t + 4
c) 9 – 4z – 4 = 2 + 7 – 1
d) 16y + 5-3 = -2y – 15
e) -x + 40 = 4x
f) 6(t + 5) = t.
g) 5(y - 9) – 3 = -8- y
h) 10 - 612-8) = 9+Z
i) 12 + 2n = 9(n – 7) – 2
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Answer 1

a)x+3=7

x= 7 - 3

x= 4

b) 2t - 5 = t + 4

2t - t = 4 + 5

t= 9

c) 9 – 4z – 4 = 2 + 7 – 1

5 - 4z = 9 - 1

- 4z = 8 - 5

- 4z = 3 (-1)

4z = - 3

z= - 3/4

d) 16y + 5-3 = -2y – 15

16y + 2 = - 2y - 15

16y + 2y = - 15 - 2

18y = - 17

y= - 17/18

e) -x + 40 = 4x

- x - 4x = - 40

- 5x = - 40

x= - 40/-5

x= 8

f) 6(t + 5) = t.

6t + 30 = t

6t - t = - 30

5t = - 30

t= - 30/5

t= - 6

g) 5(y - 9) – 3 = -8- y

5y - 45 - 3 = - 8 - y

5y - 48 = - 8 - y

5y + y = - 8 + 48

6y = 40

y= 40/6(÷2)

y= 20/3

h) 10 - 612-8= 9+Z

- 602 - 8 = 9 + z

- 610 = 9 + z

- 610 - 9 = z

- 619 = z

z= - 619

i) 12 + 2n = 9(n – 7) – 2

12 + 2n = 9n - 63 - 2

2n - 9n = - 65 - 12

- 7n = - 77

n= - 77/-7

n= 11