(3х-а)*2=9х*2-6ах+а*2
(4х+1)2*=16х*2+8х+1
9х*2-6ах+а*2+16х*2+8х+1=25х*2-10х+1
(3х-а)*2+(4х+1)*2=(5х-1)*2
9x^2-6ax+a^2+16x^2+8x+1=25x^2-10x+1
9x^2-6ax+a^2+16x^2+8x+1-25x^2+10x-1=0
-6ax+a^2+18x=0
(3х-а)*2=9х*2-6ах+а*2
(4х+1)2*=16х*2+8х+1
9х*2-6ах+а*2+16х*2+8х+1=25х*2-10х+1
(3х-а)*2+(4х+1)*2=(5х-1)*2
9x^2-6ax+a^2+16x^2+8x+1=25x^2-10x+1
9x^2-6ax+a^2+16x^2+8x+1-25x^2+10x-1=0
-6ax+a^2+18x=0