To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so add the coefficients and retain the base and exponent:

9x³ + 5x³
(9 + 5)x³
14x³

The commutative property states that, when adding or multiplying numbers, the order in which they're added or multiplied does not matter. For example, 3 + 4 and 4 + 3 give the same result, as do 3 x 4 and 4 x 3.

To add these radicals together their radicands must be the same:

2\( \sqrt{20} \) + 7\( \sqrt{5} \)
2\( \sqrt{4 \times 5} \) + 7\( \sqrt{5} \)
2\( \sqrt{2^2 \times 5} \) + 7\( \sqrt{5} \)
(2)(2)\( \sqrt{5} \) + 7\( \sqrt{5} \)
4\( \sqrt{5} \) + 7\( \sqrt{5} \)

Now that the radicands are identical, you can add them together:

The ratio of football cards to baseball cards is 3:2 and the ratio of baseball cards to basketball cards is 3:1. To solve this problem, we need the baseball card side of each ratio to be equal so we need to rewrite the ratios in terms of a common number of baseball cards. (Think of this like finding the common denominator when adding fractions.) The ratio of football to baseball cards can also be written as 9:6 and the ratio of baseball cards to basketball cards as 6:2. So, the ratio of football cards to basketball cards is football:baseball, baseball:basketball or 9:6, 6:2 which reduces to 9:2.

April scored 91% on the test meaning she earned 91% of the possible points on the test. There were 400 possible points on the test so she earned 400 x 0.91 = 364 points. Each question is worth 4 points so she got \( \frac{364}{4} \) = 91 questions right.