| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.03 |
| Score | 0% | 61% |
What is \( 5 \)\( \sqrt{18} \) - \( 9 \)\( \sqrt{2} \)
| 45\( \sqrt{2} \) | |
| 6\( \sqrt{2} \) | |
| -4\( \sqrt{2} \) | |
| -4\( \sqrt{9} \) |
To subtract these radicals together their radicands must be the same:
5\( \sqrt{18} \) - 9\( \sqrt{2} \)
5\( \sqrt{9 \times 2} \) - 9\( \sqrt{2} \)
5\( \sqrt{3^2 \times 2} \) - 9\( \sqrt{2} \)
(5)(3)\( \sqrt{2} \) - 9\( \sqrt{2} \)
15\( \sqrt{2} \) - 9\( \sqrt{2} \)
Now that the radicands are identical, you can subtract them:
15\( \sqrt{2} \) - 9\( \sqrt{2} \)If \( \left|x + 8\right| \) - 1 = -5, which of these is a possible value for x?
| 1 | |
| 2 | |
| -4 | |
| -8 |
First, solve for \( \left|x + 8\right| \):
\( \left|x + 8\right| \) - 1 = -5
\( \left|x + 8\right| \) = -5 + 1
\( \left|x + 8\right| \) = -4
The value inside the absolute value brackets can be either positive or negative so (x + 8) must equal - 4 or --4 for \( \left|x + 8\right| \) to equal -4:
| x + 8 = -4 x = -4 - 8 x = -12 | x + 8 = 4 x = 4 - 8 x = -4 |
So, x = -4 or x = -12.
What is \( \frac{2}{8} \) x \( \frac{4}{9} \)?
| \(\frac{3}{20}\) | |
| \(\frac{1}{9}\) | |
| \(\frac{3}{32}\) | |
| 1 |
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{2}{8} \) x \( \frac{4}{9} \) = \( \frac{2 x 4}{8 x 9} \) = \( \frac{8}{72} \) = \(\frac{1}{9}\)
A factor is a positive __________ that divides evenly into a given number.
fraction |
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improper fraction |
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mixed number |
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integer |
A factor is a positive integer that divides evenly into a given number. For example, the factors of 8 are 1, 2, 4, and 8.
If a rectangle is twice as long as it is wide and has a perimeter of 6 meters, what is the area of the rectangle?
| 98 m2 | |
| 50 m2 | |
| 18 m2 | |
| 2 m2 |
The area of a rectangle is width (w) x height (h). In this problem we know that the rectangle is twice as long as it is wide so h = 2w. The perimeter of a rectangle is 2w + 2h and we know that the perimeter of this rectangle is 6 meters so the equation becomes: 2w + 2h = 6.
Putting these two equations together and solving for width (w):
2w + 2h = 6
w + h = \( \frac{6}{2} \)
w + h = 3
w = 3 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 3 - 2w
3w = 3
w = \( \frac{3}{3} \)
w = 1
Since h = 2w that makes h = (2 x 1) = 2 and the area = h x w = 1 x 2 = 2 m2