Question

Which expression is equivalent to 3(x2 - 1) - (x2 - 7x + 10)?

1. 2x2 - 7x +7
2. 2x2 + 7x - 13
3. 2x2 - 7x +9
4. 2x2 + 7x - 11

Answer 1

2. 2x² + 7x - 13

Explanation:

3[x² - 1] - [x² - 7x + 10]

3x² - 3 - x² + 7x - 10

2x² - 13 + 7x

The above answer is a bit written in reverse, which is the exact same result.

So, after performing the Distributive Property, from there, you can combine all like-terms, as done above.

** Now, just in case you are wondering why that -7 has been altered to its opposite, it is because although -7x does not have another like-term to pair up with, IT IS STILL HOOKED UP TO ANOTHER NEGATIVE, so that -7x is REALLY 7x.

I am joyous to assist you anytime.