Question

What should be taken away from 3x - 4y + 5xy + 20 to obtain - x2 - y2 + 6xy + 20? ​

Answer 1

Answer:

To obtain the answer we will subtract equation 2 from the equation 1.

Answer 2

(3x² - 4y² + 5xy + 20) - ( -x² - y² + 6xy + 20 )

= 3x² - 4y² + 5xy + 20 + x² + y² - 6xy - 20

= 3x² + x² - 4y² + y² + 5xy - 6xy + 20 - 20

= 4x² - 3y² - xy - 0

Ans = 4x² - 3y² - xy .

4x² - 3y² - xy . should be taken away

from 3x² - 4y² + 5xy + 20 to get answer as

- x² - y² + 6xy + 20 .