Question

–6x²+2y² from 9x²–3y²​

Answer 1

I hope this answers your helpfull

Answer 2

Step-by-step explanation:

If it is a subtraction then ,

$9x ^{2} - 3y {}^{2} \\ - ( - 6x {}^{2} + 2y {}^{2} )$

Now,

$9x {}^{2} - 3y {}^{2} \\ 6x {}^{2} - 2y {}^{2}$

_________________

$15x {}^{2} - 5y {}^{2}$

And if it is addition then,

$9x {}^{2} - 3y { }^{2} \\ + ( - 6x {}^{2} +2y {}^{2} )$

Now,

$9x {}^{2} - 3y {}^{2} \\ - 6x {}^{2} + 2y {}^{2}$

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$3x {}^{2} - y {}^{2}$

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