| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
If \(\left|a\right| = 7\), which of the following best describes a?
a = -7 |
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a = 7 |
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a = 7 or a = -7 |
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none of these is correct |
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).
If a rectangle is twice as long as it is wide and has a perimeter of 54 meters, what is the area of the rectangle?
| 50 m2 | |
| 8 m2 | |
| 162 m2 | |
| 18 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 54 meters so the equation becomes: 2w + 2h = 54.
Putting these two equations together and solving for width (w):
2w + 2h = 54
w + h = \( \frac{54}{2} \)
w + h = 27
w = 27 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 27 - 2w
3w = 27
w = \( \frac{27}{3} \)
w = 9
Since h = 2w that makes h = (2 x 9) = 18 and the area = h x w = 9 x 18 = 162 m2
This property states taht the order of addition or multiplication does not mater. For example, 2 + 5 and 5 + 2 are equivalent.
commutative |
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distributive |
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associative |
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PEDMAS |
The commutative property states that, when adding or multiplying numbers, the order in which they're added or multiplied does not matter. For example, 3 + 4 and 4 + 3 give the same result, as do 3 x 4 and 4 x 3.
\({b + c \over a} = {b \over a} + {c \over a}\) defines which of the following?
distributive property for division |
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commutative property for division |
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commutative property for multiplication |
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distributive property for multiplication |
The distributive property for division helps in solving expressions like \({b + c \over a}\). It specifies that the result of dividing a fraction with multiple terms in the numerator and one term in the denominator can be obtained by dividing each term individually and then totaling the results: \({b + c \over a} = {b \over a} + {c \over a}\). For example, \({a^3 + 6a^2 \over a^2} = {a^3 \over a^2} + {6a^2 \over a^2} = a + 6\).
Solve for \( \frac{4!}{5!} \)
| \( \frac{1}{6} \) | |
| \( \frac{1}{5} \) | |
| \( \frac{1}{15120} \) | |
| 56 |
A factorial is the product of an integer and all the positive integers below it. To solve a fraction featuring factorials, expand the factorials and cancel out like numbers:
\( \frac{4!}{5!} \)
\( \frac{4 \times 3 \times 2 \times 1}{5 \times 4 \times 3 \times 2 \times 1} \)
\( \frac{1}{5} \)
\( \frac{1}{5} \)