: а)3(х+1) +7(х-3)=8(х+2); б)6(2х+3) -8х=4х+18.

a). 3(x+1)+7(x-3)=8(x+2)

3x + 3 + 7x – 21 = 8x + 16

3x + 7x – 8x = 16 + 21 – 3

2x = 34

x = 17

б). 6(2x+3)-8x=4x+18

12x + 18 – 8x = 4x + 18

12x – 8x – 4x = 18 – 18

a)

3x + 3 + 7x - 21 = 8x + 16

3x + 7x - 8x = 16 - 3 + 21

2x = 34

x = 17

б)

12x + 18 - 8x = 4x + 18

12x - 8x - 4x = 18 - 18

0 = 0