20-4×p×22×p=
20-88×p×p=
20-88×(12,25)=
-1058
(x-3)²-2x²+18=0
x²-6x+9-2x²+18=0
-x²-6x+27=0
x²+6x-27=0
D=36+108=144,√D=√144=12
x1=(-6+12)/2=6/2=3, x1=3
x2=(-6-12)/2=-18/2=-9, x2=-9
<span>4(a+5)²-(4a²+40a)=4(a</span><span>²+10a+25)-4a</span><span>²-40a=100</span>