Question

From the sum of 3a^2−ab−2b^2 and 2a^2+5ab−3b^2 subtract a^2−3ab−4b^2

Answer 1

4a^2+7ab-b^2

Explanation:

Add the first two equations together:

3a^2-ab-2b^2

+ 2a^2+5ab-3b^2

---------------------------

5a^2+4ab-5b^2

Subtract that answer from the remaining trinomial:

5a^2+4ab-5b^2

- a^2-3ab-4b^2

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4a^2+7ab-b^2