| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.01 |
| Score | 0% | 60% |
Simplify (9a)(9ab) + (5a2)(4b).
| 61ab2 | |
| 162a2b | |
| 101a2b | |
| 162ab2 |
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)(9ab) + (5a2)(4b)
(9 x 9)(a x a x b) + (5 x 4)(a2 x b)
(81)(a1+1 x b) + (20)(a2b)
81a2b + 20a2b
101a2b
The formula for the area of a circle is which of the following?
c = π d2 |
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c = π r2 |
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c = π d |
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c = π r |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.
Which of the following statements about math operations is incorrect?
all of these statements are correct |
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you can subtract monomials that have the same variable and the same exponent |
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you can multiply monomials that have different variables and different exponents |
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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.
Simplify (y + 2)(y - 1)
| y2 - y - 2 | |
| y2 + y - 2 | |
| y2 + 3y + 2 | |
| y2 - 3y + 2 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y + 2)(y - 1)
(y x y) + (y x -1) + (2 x y) + (2 x -1)
y2 - y + 2y - 2
y2 + y - 2
Order the following types of angle from least number of degrees to most number of degrees.
right, acute, obtuse |
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right, obtuse, acute |
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acute, right, obtuse |
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acute, obtuse, right |
An acute angle measures less than 90°, a right angle measures 90°, and an obtuse angle measures more than 90°.