Question

from the sum of 4x^2+3xy-17 and 3x^2-4xy+7, subtract the sum of 7xy-17 and 8x^2-8xy+27

Answer 1

4x^2+3xy-17+3x^2-4xy+7
7x^2-xy-10

7xy-17+8x^2-8xy+27
8x^2-xy+10

So,
8x^2-xy+10-(7x^2-xy-10)
8x^2-xy+10-7x^2+xy+10
x^2+20