| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.46 |
| Score | 0% | 69% |
Simplify (9a)(6ab) - (3a2)(3b).
| 63ab2 | |
| 45a2b | |
| 90a2b | |
| 63a2b |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(9a)(6ab) - (3a2)(3b)
(9 x 6)(a x a x b) - (3 x 3)(a2 x b)
(54)(a1+1 x b) - (9)(a2b)
54a2b - 9a2b
45a2b
Which of the following is not true about both rectangles and squares?
the lengths of all sides are equal |
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the perimeter is the sum of the lengths of all four sides |
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all interior angles are right angles |
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the area is length x width |
A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s2).
Which of the following statements about math operations is incorrect?
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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all of these statements are correct |
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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.
When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
acute, obtuse |
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supplementary, vertical |
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obtuse, acute |
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vertical, supplementary |
Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).
A coordinate grid is composed of which of the following?
y-axis |
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x-axis |
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origin |
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all of these |
The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.