Решите уравнения: (х+2)/5=(3х−5)/4 (6х+7)/7 - 3 = (5х-3)/8 (3-х)/12 =(-х+6)/8

Question

Решите уравнения: (х+2)/5=(3х−5)/4 (6х+7)/7 - 3 = (5х-3)/8 (3-х)/12 =(-х+6)/8

Answer 1

Ответ:

1.) (x+2)/5=(3x-5)/4 |*20

4*(x+2)=5*(3x-5)

4x+8=15x-25

-11x=-33

x=3

2.) (6x+7)/7-3= (5x-3)/8 |*56

8*(6x+7)-168= 7*(5x-3)

48x+56-168= 35x-21

13x = 91

x = 7

3.) (3-x)/12 = (-x+6)/8 |*96

8*(3-x) = 12*(-x+6)

24-8x = -12x+72

4x = 48

x = 12