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

7\( \sqrt{27} \) - 4\( \sqrt{3} \)
7\( \sqrt{9 \times 3} \) - 4\( \sqrt{3} \)
7\( \sqrt{3^2 \times 3} \) - 4\( \sqrt{3} \)
(7)(3)\( \sqrt{3} \) - 4\( \sqrt{3} \)
21\( \sqrt{3} \) - 4\( \sqrt{3} \)

Now that the radicands are identical, you can subtract them:

To divide terms with radicals, divide the coefficients and radicands separately:

\( \frac{49\sqrt{32}}{7\sqrt{8}} \)
\( \frac{49}{7} \) \( \sqrt{\frac{32}{8}} \)
7 \( \sqrt{4} \)

The factors of a number are all positive integers that divide evenly into the number. The factors of 32 are 1, 2, 4, 8, 16, 32.

To multiply terms with exponents, the base of both exponents must be the same. In this case they are so multiply the coefficients and add the exponents:

-8c⁶ x 6c⁴
(-8 x 6)c^{(6 + 4)}
-48c¹⁰

In order to find how many additional workers are needed to staff the extra crews you first need to calculate how many workers are on a crew. There are 10 workers at the company now and that's enough to staff 5 crews so there are \( \frac{10}{5} \) = 2 workers on a crew. 7 crews are needed for the busy season which, at 2 workers per crew, means that the roofing company will need 7 x 2 = 14 total workers to staff the crews during the busy season. The company already employs 10 workers so they need to add 14 - 10 = 4 new staff for the busy season.