My answer got deleted for some reason, so here we go again. To convert a number to a percent, you multiply the number by 100. So if you had the number 2.4, you would multiply it by 100 to get 240%. After multiplying it by 100, simply add a percent sign, and you're done!
Answer:
-72
Step-by-step explanation:
The answer is -72 because 8 * -9 = -72, I can't explain it to you any other way ;-;
We know that the trigonometric identity that uses the adjacent side and the hypotenuse is cosine. We can set this up as:

We need to solve for x, so let's isolate it:

So,
x = 10.2 units