Help plz I think the first one is correct but I'm not sure

The left side 10x+25 is the cost expression for Black Diamond, while the right hand side 5x+50 is for Bunny Hill. The x is the number of hours.

2. 2x² + 7x - 13

Step-by-step 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.