| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.19 |
| Score | 0% | 64% |
Which of the following statements about math operations is incorrect?
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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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.
What is 7a - 3a?
| 4a | |
| 4a2 | |
| 10a2 | |
| 10 |
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.
7a - 3a = 4a
Simplify (4a)(3ab) + (9a2)(7b).
| 75a2b | |
| 112ab2 | |
| 75ab2 | |
| 51a2b |
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.
(4a)(3ab) + (9a2)(7b)
(4 x 3)(a x a x b) + (9 x 7)(a2 x b)
(12)(a1+1 x b) + (63)(a2b)
12a2b + 63a2b
75a2b
The dimensions of this trapezoid are a = 5, b = 2, c = 7, d = 6, and h = 4. What is the area?
| 14 | |
| 16 | |
| 24 | |
| 19\(\frac{1}{2}\) |
The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:
a = ½(b + d)(h)
a = ½(2 + 6)(4)
a = ½(8)(4)
a = ½(32) = \( \frac{32}{2} \)
a = 16
Which types of triangles will always have at least two sides of equal length?
equilateral and right |
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equilateral, isosceles and right |
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equilateral and isosceles |
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isosceles and right |
An isosceles triangle has two sides of equal length. An equilateral triangle has three sides of equal length. In a right triangle, two sides meet at a right angle.