| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.81 |
| Score | 0% | 76% |
What is 9a6 - 7a6?
| 63a12 | |
| 2a6 | |
| a612 | |
| 2a12 |
To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.
9a6 - 7a6 = 2a6
Which of the following statements about math operations is incorrect?
all of these statements are correct |
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you can multiply monomials that have different variables and different exponents |
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you can subtract monomials that have the same variable and the same exponent |
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you can add monomials that have the same variable and the same exponent |
You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a2 - a2 = 3a2 but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.
The formula for volume of a cube in terms of height (h), length (l), and width (w) is which of the following?
h2 x l2 x w2 |
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lw x wh + lh |
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2lw x 2wh + 2lh |
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h x l x w |
A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.
What is 5a + 8a?
| 40a | |
| 13a | |
| a2 | |
| 13a2 |
To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.
5a + 8a = 13a
A right angle measures:
45° |
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360° |
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90° |
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180° |
A right angle measures 90 degrees and is the intersection of two perpendicular lines. In diagrams, a right angle is indicated by a small box completing a square with the perpendicular lines.