-18 = 8a-9 -5a 7(a - 3)=36

Question

-18 = 8a-9 -5a
7(a - 3)=36

Answer 1

-18 = 8a-9 -5a
-18+9=8а-5а
9=3а
а=3

7(a - 3)=35
7а-21=35
7а=35+21
7а=56
а=8

Answer 2

-18=8а-9-5а
5а-8а=-9+18
-3а=9/÷(-3)
а=-3
Ответ: -3