| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.70 |
| Score | 0% | 54% |
If \( \left|x - 5\right| \) + 5 = -4, which of these is a possible value for x?
| -10 | |
| -4 | |
| 8 | |
| -5 |
First, solve for \( \left|x - 5\right| \):
\( \left|x - 5\right| \) + 5 = -4
\( \left|x - 5\right| \) = -4 - 5
\( \left|x - 5\right| \) = -9
The value inside the absolute value brackets can be either positive or negative so (x - 5) must equal - 9 or --9 for \( \left|x - 5\right| \) to equal -9:
| x - 5 = -9 x = -9 + 5 x = -4 | x - 5 = 9 x = 9 + 5 x = 14 |
So, x = 14 or x = -4.
What is \( 4 \)\( \sqrt{8} \) + \( 2 \)\( \sqrt{2} \)
| 10\( \sqrt{2} \) | |
| 8\( \sqrt{8} \) | |
| 6\( \sqrt{4} \) | |
| 8\( \sqrt{2} \) |
To add these radicals together their radicands must be the same:
4\( \sqrt{8} \) + 2\( \sqrt{2} \)
4\( \sqrt{4 \times 2} \) + 2\( \sqrt{2} \)
4\( \sqrt{2^2 \times 2} \) + 2\( \sqrt{2} \)
(4)(2)\( \sqrt{2} \) + 2\( \sqrt{2} \)
8\( \sqrt{2} \) + 2\( \sqrt{2} \)
Now that the radicands are identical, you can add them together:
8\( \sqrt{2} \) + 2\( \sqrt{2} \)If a rectangle is twice as long as it is wide and has a perimeter of 42 meters, what is the area of the rectangle?
| 18 m2 | |
| 98 m2 | |
| 50 m2 | |
| 32 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 42 meters so the equation becomes: 2w + 2h = 42.
Putting these two equations together and solving for width (w):
2w + 2h = 42
w + h = \( \frac{42}{2} \)
w + h = 21
w = 21 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 21 - 2w
3w = 21
w = \( \frac{21}{3} \)
w = 7
Since h = 2w that makes h = (2 x 7) = 14 and the area = h x w = 7 x 14 = 98 m2
Which of the following statements about exponents is false?
b1 = 1 |
|
b0 = 1 |
|
b1 = b |
|
all of these are false |
A number with an exponent (be) consists of a base (b) raised to a power (e). The exponent indicates the number of times that the base is multiplied by itself. A base with an exponent of 1 equals the base (b1 = b) and a base with an exponent of 0 equals 1 ( (b0 = 1).
What is (z2)4?
| z8 | |
| z-2 | |
| z6 | |
| z2 |
To raise a term with an exponent to another exponent, retain the base and multiply the exponents:
(z2)4