(x-2)^2+2(x+1)^2=8; x^2+x=1.5x^2; 25x^2=(4x)^2+(3x)^2 нужны

1)х^2-4х+4+2(х^2+2х+1)=8
х^2-4х+4+2х^2+4х+2-8=0
3х^2=2
х^2=2/3
х=корень(2/3)
2) х^2+х=1,5х^2
0,5х^2+х=0
х(0,5х+1)=0
х1=0
0,5х=-1
х2=-2
3) 25х^2=(4х)^2+(3х)^2
25х^2=16х^2+9х^2
25х^2=25х^2