I think the answer is 25.5. Although, I don't know how you would have half a bike unless there was a 3 wheel bike which would make the answer 24.
It would be 28-10=x because your ending up with 28 after earning 10 you would get that. Hope this works!
Hi there!
First we need to remember the following.

Now substitute both of the formulas.

Work out the parenthesis.

And finally collect terms.

~ Hope this helps you!
Answer: 3t²(2st⁷ - s⁶ - 2t⁵)
<u>Step-by-step explanation:</u>
5s⁶t² + 6st⁹ - 8s⁶t² - 6t⁷ <em>5s⁶t² and - 8s⁶t² are like terms which = -3s⁶t² when combined</em>
= 6st⁹ - 3s⁶t² - 6t⁷ <em>next, factor out the GCF of 3t²</em>
= 3t²(2st⁷ - s⁶ - 2t⁵)