Question

if A = x²+y²–z²,B=3x²–2y²+5y² and C=3y²–5y²–z²,find the value of 2A‐3B+4C
​

Answer 1

Question

If A = x²+y²–z²,B=3x²–2y²+5y² and C=3y²–5y²–z²,find the value of 2A‐3B+4C?

Solution

Given:-

________________

A = x²+y²–z²

So,

2A = 2x²+2y²-2z²

B= 3x²-2y²+5y²

So,

3B= 9x²-6y²+15y²

=9x²+9y²

C=3y²–5y²–z²

So,

4C=12y²–20y²–4z²

______________

Therefore,

2A‐3B+4C=

= 2x²+2y²-2z²-(9x²+9y²)+12y²–20y²–4z²

= 2x²+2y²-2z²-9x²-9y²+12y²–20y²–4z²

= -7x²-15y²-6z²

________________________

Therefore, -7x²-15y²-6z² is the answer.