| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.65 |
| Score | 0% | 53% |
What is \( 4 \)\( \sqrt{45} \) - \( 3 \)\( \sqrt{5} \)
| 12\( \sqrt{9} \) | |
| \( \sqrt{9} \) | |
| 9\( \sqrt{5} \) | |
| \( \sqrt{225} \) |
To subtract these radicals together their radicands must be the same:
4\( \sqrt{45} \) - 3\( \sqrt{5} \)
4\( \sqrt{9 \times 5} \) - 3\( \sqrt{5} \)
4\( \sqrt{3^2 \times 5} \) - 3\( \sqrt{5} \)
(4)(3)\( \sqrt{5} \) - 3\( \sqrt{5} \)
12\( \sqrt{5} \) - 3\( \sqrt{5} \)
Now that the radicands are identical, you can subtract them:
12\( \sqrt{5} \) - 3\( \sqrt{5} \)The __________ is the smallest positive integer that is a multiple of two or more integers.
absolute value |
|
least common factor |
|
least common multiple |
|
greatest common factor |
The least common multiple (LCM) is the smallest positive integer that is a multiple of two or more integers.
Solve for \( \frac{6!}{2!} \)
| \( \frac{1}{1680} \) | |
| \( \frac{1}{56} \) | |
| 1680 | |
| 360 |
A factorial is the product of an integer and all the positive integers below it. To solve a fraction featuring factorials, expand the factorials and cancel out like numbers:
\( \frac{6!}{2!} \)
\( \frac{6 \times 5 \times 4 \times 3 \times 2 \times 1}{2 \times 1} \)
\( \frac{6 \times 5 \times 4 \times 3}{1} \)
\( 6 \times 5 \times 4 \times 3 \)
360
What is 4\( \sqrt{4} \) x 8\( \sqrt{8} \)?
| 32\( \sqrt{4} \) | |
| 128\( \sqrt{2} \) | |
| 32\( \sqrt{12} \) | |
| 12\( \sqrt{4} \) |
To multiply terms with radicals, multiply the coefficients and radicands separately:
4\( \sqrt{4} \) x 8\( \sqrt{8} \)
(4 x 8)\( \sqrt{4 \times 8} \)
32\( \sqrt{32} \)
Now we need to simplify the radical:
32\( \sqrt{32} \)
32\( \sqrt{2 \times 16} \)
32\( \sqrt{2 \times 4^2} \)
(32)(4)\( \sqrt{2} \)
128\( \sqrt{2} \)
If \( \left|z + 6\right| \) + 8 = 9, which of these is a possible value for z?
| -3 | |
| 0 | |
| -2 | |
| -5 |
First, solve for \( \left|z + 6\right| \):
\( \left|z + 6\right| \) + 8 = 9
\( \left|z + 6\right| \) = 9 - 8
\( \left|z + 6\right| \) = 1
The value inside the absolute value brackets can be either positive or negative so (z + 6) must equal + 1 or -1 for \( \left|z + 6\right| \) to equal 1:
| z + 6 = 1 z = 1 - 6 z = -5 | z + 6 = -1 z = -1 - 6 z = -7 |
So, z = -7 or z = -5.