| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.87 |
| Score | 0% | 57% |
What is \( 9 \)\( \sqrt{20} \) - \( 7 \)\( \sqrt{5} \)
| 63\( \sqrt{5} \) | |
| 63\( \sqrt{4} \) | |
| 63\( \sqrt{20} \) | |
| 11\( \sqrt{5} \) |
To subtract these radicals together their radicands must be the same:
9\( \sqrt{20} \) - 7\( \sqrt{5} \)
9\( \sqrt{4 \times 5} \) - 7\( \sqrt{5} \)
9\( \sqrt{2^2 \times 5} \) - 7\( \sqrt{5} \)
(9)(2)\( \sqrt{5} \) - 7\( \sqrt{5} \)
18\( \sqrt{5} \) - 7\( \sqrt{5} \)
Now that the radicands are identical, you can subtract them:
18\( \sqrt{5} \) - 7\( \sqrt{5} \)Simplify \( \sqrt{18} \)
| 9\( \sqrt{4} \) | |
| 3\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| 2\( \sqrt{4} \) |
To simplify a radical, factor out the perfect squares:
\( \sqrt{18} \)
\( \sqrt{9 \times 2} \)
\( \sqrt{3^2 \times 2} \)
3\( \sqrt{2} \)
What is -5a4 + 2a4?
| -3a4 | |
| -7a-4 | |
| -7a4 | |
| 7a4 |
To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so add the coefficients and retain the base and exponent:
-5a4 + 2a4
(-5 + 2)a4
-3a4
10 members of a bridal party need transported to a wedding reception but there are only 2 3-passenger taxis available to take them. How many will need to find other transportation?
| 4 | |
| 3 | |
| 2 | |
| 7 |
There are 2 3-passenger taxis available so that's 2 x 3 = 6 total seats. There are 10 people needing transportation leaving 10 - 6 = 4 who will have to find other transportation.
Which of the following statements about exponents is false?
b1 = b |
|
b0 = 1 |
|
all of these are false |
|
b1 = 1 |
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).