Odpowiedź :
a) 5x-x^2-15+3x-2=2x-8-x^2+4x+3
8x-17=6x-5
2x=12
x=6
b) 6x+12-x^2-2x+x^2-4x+3x-12=2x+5
3x-2x=5
x=5
c) x^2+2x-5x-10-(6-3x-2x+x^2)=x-12
x^2-3x-10-6+3x+2x-x^2=x-12
2x-16=x-12
x=4
d) 2x^2+2x-5x-5-2=8-2x-8x+2x^2+ 2x
-3x-7=8-8x
5x=15
x=3
8x-17=6x-5
2x=12
x=6
b) 6x+12-x^2-2x+x^2-4x+3x-12=2x+5
3x-2x=5
x=5
c) x^2+2x-5x-10-(6-3x-2x+x^2)=x-12
x^2-3x-10-6+3x+2x-x^2=x-12
2x-16=x-12
x=4
d) 2x^2+2x-5x-5-2=8-2x-8x+2x^2+ 2x
-3x-7=8-8x
5x=15
x=3