Me ajuda
a) (x-4)²=2x(1-x)
b)1/5(um quinto)=-4x/5(quatro'com x' quinto)+x²
1/5=-4x/5+x²
a)
(x-4)*(x-4)=2x-2x^2
x^2-4x-4x+16=2x-2x^2
x^2-8x+16-2x+2x^2=0
x^2+2x^2-8x-2x+16=0
3x^2-10x+16=0
b)
1/5=4x/5+x^2 /*5
1/5*5=(4x/5)*5+x^2*5
1=4x+5x^2
-5x^2-4x+1=0
Comments
a)
(x-4)*(x-4)=2x-2x^2
x^2-4x-4x+16=2x-2x^2
x^2-8x+16-2x+2x^2=0
x^2+2x^2-8x-2x+16=0
3x^2-10x+16=0
b)
1/5=4x/5+x^2 /*5
1/5*5=(4x/5)*5+x^2*5
1=4x+5x^2
-5x^2-4x+1=0