решите уравнения -8х=3.2. 4-5х=0. 10х+7=3. 3-4х=х-12. (х+7)-(3х+5)=2

Question

решите уравнения -8х=3.2. 4-5х=0. 10х+7=3. 3-4х=х-12. (х+7)-(3х+5)=2

Answer 1

-8x=3.2 | :(-8)
x=-0.4

4-5x=0
-5x=-4 | :(-5)
x=0.8

10x+7=3
10x=-4 | :10
x=-0.4

3-4x=x-12
-4x-x=-12-3
-5x=-15 | :(-5)
x=3

(x+7)-(3x+5)=2
x+7-3x-5=2
-3x+x=2-7+5
-2x=0 | :(-2)
x=0