Question

rezolvati ecuatiile:a)(x-2)(x+2)+6=(2x-3)²-3x(x-1);
b) 1-x=2x-(x-3)* x+(x-4)²
c) -x-(-2x-3)²=-4x²-3(x-2);

Answer 1

a)(x-2)(x+2)+6=(2x-3)²-3x(x-1)
x²-4+6=4x²-12x+9-3x²+3x
x²-4x²+3x²=-12x+3x+9-2
0=-9x+7 =>-9x=-7 =>x=7/9

b) 1-x=2x-(x-3)* x+(x-4)²
1-x=2x-x²+3x+x²-8x+16
1-x=-3x+16
1-16=x-3x
-15=-2x =>x=15/2

c) -x-(-2x-3)(-2x-3)=-4x²-3(x-2)
-x-(4x²+12x+9)=-4x²-3x+6
-x-4x²-12x-9=-4x²-3x+6
-13x-9=-3x+6
-13x+3x=9+6
-10x=15 =>x=-15/10=-3/2