(578 - 622)² + 4 * 578 * 622 =
= 578² - 2 * 578 * 622 + 622² + 4 * 578 * 622 =
= 578² + 2 * 578 * 622 + 622² =
= (578 + 622)² = 1200² = 1 440 000
(1-2x)-2(3x-4)=8(3-x)
1-2x-6x+8=24-8x
8x-2x-6x=-8-1
0=-9
x∈∅
8)(3/10)²-(4/5)²=(3/10-4/5)(3/10+4/5)=(-5/10)(11/10)=-55/100=-0,55
12)(5*1/6)²-(7*1/3)²=(5/6-7/3)(5/6+7/3)=(-9/6)(19/6)=(-3/2)(19/6)=-57/12
14)54²-46²=(54-46)(54+46)=8×100=800
(x-1)²= -4x
x²-2x+1= -4x
x²+2x+1=0
(x+1)²=0
x+1=0
x= -1