Răspuns:
(0.2x+0.2)+(0.x+1)+0.xx=0.3x-0.6+1.09
0.2x+0.x^2+1.2=0.3x+0.50
0.2x+0.x^2+1.2-0.3x+0.5=0
0.x^2-0.1x+1.7=0|*10
a=0.1
b=-0.1
c=1.7
Delta= b^2-4ac
Delta=0.01-4*-0.1*1.7
Delta=0.01+0.4*1.7
Delta=0.01+0.7=0.71
x12=-b+√b^2-4ac/2a
x12=0.1+√0.71/0.2
x12=0.8/0.2=0.4