Question

1)Resolva as seguintes equações, sendo U= a

a) 3 (x - 1) - 7 = 15
b) 7 (x - 4) = 2x - 3
c) 5x - 3 (x + 2) = 15
d) 7 (x - 1 ) - 2 ( x - 3 ) = x - 5
e) (x - 3) - ( x + 2) + 2 ( x - 1) - 5 = 0

Answer 1

Vamos là.

a)

3x - 3 - 7 = 15

3x = 15 + 10 = 25

x = 25/3

b)

7x - 28 = 2x - 3

5x = 25

x = 5

c)

5x - 3x - 6 = 15

2x = 21

x = 21/2

d)

7x - 7 - 2x + 6 = x - 5

4x = -5 + 1 = -4

x = -1

e)

x - 3 - x - 2 + 2x - 2 - 5 = 0

2x = 12

x = 6