| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.28 |
| Score | 0% | 66% |
What is -8b6 x 5b6?
| -3b12 | |
| -40b12 | |
| -3b36 | |
| -40b6 |
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:
-8b6 x 5b6
(-8 x 5)b(6 + 6)
-40b12
| 3.6 | |
| 2.7 | |
| 1.0 | |
| 1 |
1
What is \( \frac{4}{8} \) - \( \frac{6}{16} \)?
| 1 \( \frac{9}{16} \) | |
| \(\frac{1}{8}\) | |
| \( \frac{4}{11} \) | |
| \( \frac{5}{10} \) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80] and the first few multiples of 16 are [16, 32, 48, 64, 80, 96]. The first few multiples they share are [16, 32, 48, 64, 80] making 16 the smallest multiple 8 and 16 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{4 x 2}{8 x 2} \) - \( \frac{6 x 1}{16 x 1} \)
\( \frac{8}{16} \) - \( \frac{6}{16} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{8 - 6}{16} \) = \( \frac{2}{16} \) = \(\frac{1}{8}\)
What is \( \frac{10\sqrt{10}}{5\sqrt{2}} \)?
| 2 \( \sqrt{5} \) | |
| \(\frac{1}{2}\) \( \sqrt{\frac{1}{5}} \) | |
| 5 \( \sqrt{2} \) | |
| \(\frac{1}{5}\) \( \sqrt{\frac{1}{2}} \) |
To divide terms with radicals, divide the coefficients and radicands separately:
\( \frac{10\sqrt{10}}{5\sqrt{2}} \)
\( \frac{10}{5} \) \( \sqrt{\frac{10}{2}} \)
2 \( \sqrt{5} \)
If \(\left|a\right| = 7\), which of the following best describes a?
a = 7 |
|
a = -7 |
|
none of these is correct |
|
a = 7 or a = -7 |
The absolute value is the positive magnitude of a particular number or variable and is indicated by two vertical lines: \(\left|-5\right| = 5\). In the case of a variable absolute value (\(\left|a\right| = 5\)) the value of a can be either positive or negative (a = -5 or a = 5).