Question

what should be taken away from 3 x square minus 4 y square + 5 X y + 20 to get minus x square minus y square + 6 X y + 20

Answer 1

This is the answer
for the question

Answer 2

first we take
3x^2-4y^2+5xy+20 - (1)

we want to get

-x^2-y^2+6xy+20 -(2)
then we want to minus
(2) from(1)
ie,

3x^2-4y^2+5xy+20
-
-1x^2-1y^2+6xy+20
=
4x^2-3y^2+1xy0