Question

1) 2 x + 3x - 18 = x - 7x + 15;
2) 4x + 5x1 - 3 = 2 x + 11.

Answer 1

1)2x+3x-x+7x=18+15

11x=33

x=3

Answer 2

1)

$2x+3x-18=x-7x+15\\2x+3x-x+7x=15+18\\11x=33\\x=33:11\\x=3\\$

Проверка

$2*3+3*3-18=3-7*3+15\\6+9-18=3-21+15\\15-18=18-21\\-3=-3\\$

2)

$4x+5x-3=2x+11\\4x+5x-2x=11+3\\7x=11\\x=14:7\\x=2$

Проверка

$4*2+5*2-3=2*2+11\\8+10-3=4+11\\18-3=15\\15=15$