| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.85 |
| Score | 0% | 57% |
Simplify (7a)(2ab) + (3a2)(8b).
| -10ab2 | |
| 99a2b | |
| -10a2b | |
| 38a2b |
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.
(7a)(2ab) + (3a2)(8b)
(7 x 2)(a x a x b) + (3 x 8)(a2 x b)
(14)(a1+1 x b) + (24)(a2b)
14a2b + 24a2b
38a2b
Which of the following is not required to define the slope-intercept equation for a line?
x-intercept |
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slope |
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\({\Delta y \over \Delta x}\) |
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y-intercept |
A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.
Which of the following statements about math operations is incorrect?
you can add monomials that have the same variable and the same exponent |
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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 multiply monomials that have different variables and different exponents |
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).
supplementary, vertical |
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acute, obtuse |
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vertical, supplementary |
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obtuse, acute |
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).
For this diagram, the Pythagorean theorem states that b2 = ?
a2 - c2 |
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c - a |
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c2 + a2 |
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c2 - a2 |
The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c2) is equal to the sum of the two perpendicular sides squared (a2 + b2): c2 = a2 + b2 or, solved for c, \(c = \sqrt{a + b}\)