(x+2)^2=(2x-5)^2
x^2+4x+4=4x^2-20x+25
(x^2-4x+4)-(4x^2-20x+25)=0
-3x^2+24x-21=0
-3*(x^2+8x-7)=0
x^2+8x-7=0:-3
x^2+8x-7=0
Coeficienti:
A=1
B=-8
C=7
x=[8+/-√(-8^2-4*1*7)]:2*1
x=[8+/-√(64-28)]:2
x=(8+/-√36):2
x=(8+/-6):2
x1=(8+6):2
x1=14:2
x1=7
x2=(8-6):2
x2=2:2
x2=1
Solutia 1:
x=7
Solutia 2:
x=1
