| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.87 |
| Score | 0% | 57% |
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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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 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.
Solve 9a - 7a = 7a + 3y - 7 for a in terms of y.
| -\(\frac{1}{2}\)y + 1 | |
| y - 1\(\frac{2}{3}\) | |
| 5y - 3\(\frac{1}{2}\) | |
| -1\(\frac{7}{8}\)y + \(\frac{5}{8}\) |
To solve this equation, isolate the variable for which you are solving (a) on one side of the equation and put everything else on the other side.
9a - 7y = 7a + 3y - 7
9a = 7a + 3y - 7 + 7y
9a - 7a = 3y - 7 + 7y
2a = 10y - 7
a = \( \frac{10y - 7}{2} \)
a = \( \frac{10y}{2} \) + \( \frac{-7}{2} \)
a = 5y - 3\(\frac{1}{2}\)
When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
vertical, supplementary |
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acute, obtuse |
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supplementary, vertical |
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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).
A(n) __________ is two expressions separated by an equal sign.
formula |
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problem |
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equation |
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expression |
An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.
If the length of AB equals the length of BD, point B __________ this line segment.
trisects |
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bisects |
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intersects |
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midpoints |
A line segment is a portion of a line with a measurable length. The midpoint of a line segment is the point exactly halfway between the endpoints. The midpoint bisects (cuts in half) the line segment.