## Intermediate Algebra for College Students (7th Edition)

$x^2+y^2+8x+8y+2xy+16$
Given:$(x+y+4)^2$ Apply Formula: $(a+b)^2=a^2+b^2+2ab$ This implies $[x+(y+4)]^2=x^2+y^2+8y+16+2xy+8x$ or, $=x^2+y^2+8y+16+2xy+8x$ Hence, the result is : $x^2+y^2+8x+8y+2xy+16$