Question

What should be taken away from (3x2 – 4y2 + 5xy +20) to obtain (– x2 – y2 +6xy +20)?

Answer 1

Step-by-step explanation:

4x^2-3y^2-xy should be taken away from given number

Answer 2

Let A be taken away.

∴ (3x2 – 4y2 + 5 xy + 20)-A

= -x2 – y2 + 6xy + 20

⇒ A = (3x2 – 4y2 + 5xy + 20) – (-x22 – y2 + 6xy + 20)

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

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

= 4x2 – 3y2 – xy is required expression.