Question

resolva as equaçoes : a) 3,5x + 8 = 2 (x+7) b) 3 /4 x - 1/2 x = -2

valendo 10 + 20 pontos

Answer 1

3,5 = 35/10 = 7/2

(7/2)x - 2x = +14-8

(7/2)x - 2/2.2x =  6

(7/2)x - 4/2x = 6

3/2x = 6
3x = 6*2
3x = 12

x = 12/3

x= 4

b) 3/4x -1/2 = -2
3/4x = -2 + 1/2
3/4x =-2.2/2 + 1/2
3/4x = -4/2 = 1/2
3/4x = -3/2
3x = -3/2 . 4
3x = -12/2
3x = -6
x = -6/2
x = -3