Question

URGENTE!!
1) Resolva as equaçoes abaixo (sem utilizar a fórmula de Bháskara).
a)-2x²+484=0
b)x(4x-2)=100-2x
c)3x(x+2)=6x
d)(x-6)² =2(x+18)
e)x² +14x+49=0

Answer 1

a) -2x²+484;
(x+z)*(-x+z)=0;
-x²+(z*x)-(z*x)+z²=0;
:. -x²+z²=-2x²+484;
(-x√2+22)²=0;
-x√2=-22 (-1);
:. x=22/√2.
________
b) x*(4x-2)=100-2x;
4x²-2x=100-2x;
4x²=100;
2x=√100;
2x=10;
:. x=5.
_____
c)3x*(x+2)=6x;
3x²+6x=6x;
3x²=0;
:. x=0.
_____
d) (x-6)²=2(x+18);
(x-6)²=2x+36;
x²-6x+36=2x+36;
x²-8x=0;
(x-4)²-16=0;
x-4=√16;
x=4+4;
:. x=8.
______
e) x²+14x+49=0;
(x+7)²=0;
x=0-7;
:. x=-7.