| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.26 |
| Score | 0% | 65% |
If a rectangle is twice as long as it is wide and has a perimeter of 18 meters, what is the area of the rectangle?
| 128 m2 | |
| 8 m2 | |
| 18 m2 | |
| 162 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 18 meters so the equation becomes: 2w + 2h = 18.
Putting these two equations together and solving for width (w):
2w + 2h = 18
w + h = \( \frac{18}{2} \)
w + h = 9
w = 9 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 9 - 2w
3w = 9
w = \( \frac{9}{3} \)
w = 3
Since h = 2w that makes h = (2 x 3) = 6 and the area = h x w = 3 x 6 = 18 m2
If \( \left|b + 6\right| \) + 3 = -2, which of these is a possible value for b?
| -1 | |
| -2 | |
| -18 | |
| 4 |
First, solve for \( \left|b + 6\right| \):
\( \left|b + 6\right| \) + 3 = -2
\( \left|b + 6\right| \) = -2 - 3
\( \left|b + 6\right| \) = -5
The value inside the absolute value brackets can be either positive or negative so (b + 6) must equal - 5 or --5 for \( \left|b + 6\right| \) to equal -5:
| b + 6 = -5 b = -5 - 6 b = -11 | b + 6 = 5 b = 5 - 6 b = -1 |
So, b = -1 or b = -11.
What is the next number in this sequence: 1, 4, 10, 19, 31, __________ ?
| 46 | |
| 51 | |
| 54 | |
| 37 |
The equation for this sequence is:
an = an-1 + 3(n - 1)
where n is the term's order in the sequence, an is the value of the term, and an-1 is the value of the term before an. This makes the next number:
a6 = a5 + 3(6 - 1)
a6 = 31 + 3(5)
a6 = 46
What is \( \frac{4}{5} \) ÷ \( \frac{1}{7} \)?
| 28 | |
| 5\(\frac{3}{5}\) | |
| \(\frac{4}{21}\) | |
| \(\frac{16}{35}\) |
To divide fractions, invert the second fraction and then multiply:
\( \frac{4}{5} \) ÷ \( \frac{1}{7} \) = \( \frac{4}{5} \) x \( \frac{7}{1} \)
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{4}{5} \) x \( \frac{7}{1} \) = \( \frac{4 x 7}{5 x 1} \) = \( \frac{28}{5} \) = 5\(\frac{3}{5}\)
What is (b2)2?
| b0 | |
| 8 | |
| 2b2 | |
| b4 |
To raise a term with an exponent to another exponent, retain the base and multiply the exponents:
(b2)2