Найдите корни уравнений 9-7у=2,5-3у3,2-5а=-1,8а+40,8х-3,5=-1,2х+0,58,6х-3,7=7,6х-5

Question

Найдите корни уравнений
9-7у=2,5-3у
3,2-5а=-1,8а+4
0,8х-3,5=-1,2х+0,5
8,6х-3,7=7,6х-5

Answer 1

9-7y=2.5-3y
-7y+3y=2.5-9
-4y=-6.5/:(-4)
y=1.625

3.2-5a=-1.8a+4
-5a+1.8a=-3.2+4
-3.2a=0.8/:(-3.2)
a=-0.25

0.8x-3.5=-1.2x+0.5
0.8x+1.2x=0.5+3.5
2x=4/:2
x=2

8.6x-3.7=7.6x-5
8.6x-7.6x=-5+3.7
1x=-1.3
x=-1.3

Answer 2

1)-7у+3у=2.5-9
   -4у=-6.5
     у=1,625
2)-5а+1.8=4-3.2
   -3.2а=0.8
    а=-0.4
3)  0.8х+1.2х=3.5+0.5
      2х=4
      х=2
4)8.6х-7.6х=3.7-5
х=-1.3