Question

1) 18+х=23
2) 2(3+х)=12
3) 14(1+х)=28
4) 3х=15
5) 3х=15-2х
6) -2(4+3х)=16
7) (3+х)(2-х)=0
8) 6-х=0
9) х(х+1)=0
10) (5+х)(-2)=0
11) 11(2х+1)=55
12) 3х+4=14+5х
13) 5х(3х-2)=140+15х(4+х)
14) (х-6)(х+9)=0
15) (3х+5)(10-0,4х)=0
16) 2(4х-12)=х+13
17) 18-16х=-30х-10
18) -7х+2=3х-1
19) 6х-19=-2х-15
20) 10х+7=8х-9​

Answer 1

Ответ:

С 1 по 15 во вложении

16.

$2(4x - 12) = x + 13 \\ 8x - 24 = x + 13 \\ 8x - x = 13 + 24 \\ 7x = 37 \\ x = 37 \div 7 \\ x = 5 \frac{2}{7}$

17.

$18 - 16x = - 30x - 10 \\ - 16x + 30x = - 10 - 18 \\ 14x = - 28 \\ x = - 28 \div 14 \\ x = - 2$

18.

$- 7x + 2 = 3x - 1 \\ - 7x - 3x = - 1 - 2 \\ - 10x = - 3 \\ x = - 3 \div ( - 10) \\ x = 0.3$

19.

$6x - 19 = - 2x - 15 \\ 6x + 2x = - 15 + 19 \\ 8x = 4 \\ x = 4 \div 8 \\ x = 0.5$

20.

$10x + 7 = 8x - 9 \\ 10x - 8x = - 9 - 7 \\ 2x = - 16 \\ x = - 16 \div 2 \\ x = - 8$