Question

Представить в виде многочлена: (10x+3y)(3y-10x)-(7x-8y)(7x+8y)

Answer 1

9у^2-100x^2-49x^2+64y^2=73y^2-149x^2

Answer 2

$(10x+3y)(3y-10x)-(7x-8y)(7x+8y)=(3y+10x)(3y-10x)-(7x-8y)(7x+8y)=9y^{2}-100x^{2}-(49x^{2}-64y^{2})=9y^{2}-100x^{2}-49x^{2}+64y^{2}=(9y^{2}+64y^{2})+(-100x^{2}-49x^{2})=73y^{2}-149x^{2}$