Răspuns :
2(0,5x+3)+1- 3(0,5x+3)-1=7
x+6+1-1,5x-9-1=7
0,5x-3=7
0,5x=3+7=10
0,5x=10
x=20
x+6+1-1,5x-9-1=7
0,5x-3=7
0,5x=3+7=10
0,5x=10
x=20
2f(x+1)-3f(x+1) =>2[0.5x(x+1)]-3[0.5x(x+1)] =>2(0.5x^2+0.5)-3(0.5x^2+0.5) =>x^2+1-1.5x^2-1.5 => 0.5x^2-0.5