Answer:
13
Step-by-step explanation:
diameter = r * 2 = 13 * 2 = 26 (diameter is double radius)
Circle area = π * r^2 = π * 169 ≈ 530.9
The subtraction sign in front of the second set of parenthesis changes the signs on the terms inside those parenthesis. So this could be rewritten as

. None of the exponents on the x are the same, so we will just express it in terms of descending powers of x.

. This is also the same as

if you don't like to start with a negative. Either one is correct.
Answer: combine
Step-by-step explanation:
When you combine like terms, it shortens or simplified the equation
Example: 2x-5+15
Combine actual numbers -5 and 15.
2x+10
Imagine a machine that you put number into. However, the machine has a function that creates a new number. Remember that the number that comes out depends on the number that is put in. With this information, i'm pretty sure its the third bubble. im sorry that my information might not be accurate.