Simplify
(x2+y2-2xy5)-(-4x23-4y25+8xy4)
Consider =(x2+y2-2xy5)-(-4x23-4y25+8xy4)
=x2+y2+2xy5+4x23+4y25-8xy4
=x2+4x23+y2+4y25+2xy5-8xy4
Taking LCM
=3x2+4x23+5y2+4y25+8xy-40xy20=7x23+9y25+-32xy20=7x23+9y25-32xy20
Hence, (x2+y2-2xy5)-(-4x23-4y25+8xy4) is equal to 7x23+9y25-32xy20