Question

решить уравнение ;
1.8y-4=9y-2(2y-7)
2. 2+3z=-2z-13

Answer 1

1. 8y-4=9y-4y+14

8y-4=5y+14

8y-5y=14+4

3y=18

y=6

2. 3z+2z=-13-2

5z=-15

z=-3