Question

Ex 15 a,c va rog!!! .......

Answer 1

a)  x^2-18xy+81y^2=(x-9y)^2
c)  4xy+2x^2+2y^2=2(2xy+x^2+y^2)=2(x+y)^2;

Answer 2

a) $x^{2} -18xy+81 y^{2} = x^{2} -2*1*9xy+ 9^{2} y^{2} =( x-9y)^{2}$

b)$4xy+2 x^{2}+2 y^{2}=2(2xy+ x^{2} + y^{2} ) =2( x+y)^{2}$