(a+5)²-(a-3)²=a²+10a+25-a²+9a-9=19a+16
(x-7)(x+7)-(x-4)²=x²-49-x²+8x-16=8x-65
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(x^2+4-4x)(x^2-4x)+3=0
x^2-4x=t
(t+4)*t+3=0
t^2+4t+3=0
t1=-3 t2=-1
x^2-4x=-1
x^2-4x+1=0
x=2+-√3 x1=2-√3 x2=2+√3
x^2-4x+3=0
x3=1 x4=3
отметь "лучшим"
1. x2 + 11x + 24=0
D=b2 - 4ac
x(1)=-8
x(2)=-3