Question

Решите уровнения:

1) -7(2 - 3x) = 56;

2) (5+7a) • 15 = -30.

Answer 1

1)
 -7(2 - 3x) = 56;
-14+21x=56
21x=56+14
21x=70
x=70:21
x=3 1/3
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2)
(5+7a) • 15 = -30.
5+7a=-30:15
5+7a=-2
7a=-2-5
7a=-7
a=-7:7
x=-1

Answer 2

-14+21х=56
21х=56+14
21х=70
Х=3,3

75+105а=-30
105а=-30-75
105а=-105
А=-1