Question

=--------------00000000000-0-=0-=-=0

Answer 1

6)(2x+3)^2-(x-2)^2=5
4x^2+12x+9-x^2+4x-4-5=0
3x^2+16x=0
x(3x+16)=0
x=0
3x=-16
x=-16/3


7)y=x^2, y=kx-1
x^2=kx-1
x^2-kx+1=0
D=k^2-4
k^2-4=0
k^2=4
k1=2
K2=-2