| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.05 |
| Score | 0% | 61% |
Which of the following statements about math operations is incorrect?
all of these statements are correct |
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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 |
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you can subtract 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 8a2 + 7a2?
| 56a2 | |
| a24 | |
| 15a2 | |
| 15a4 |
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.
8a2 + 7a2 = 15a2
Which types of triangles will always have at least two sides of equal length?
equilateral, isosceles and right |
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equilateral 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.
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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supplementary, vertical |
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obtuse, acute |
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acute, obtuse |
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).
Solve for x:
3x + 3 = \( \frac{x}{-5} \)
| -\(\frac{15}{16}\) | |
| 1\(\frac{7}{17}\) | |
| -\(\frac{48}{65}\) | |
| -\(\frac{24}{25}\) |
To solve this equation, 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.
3x + 3 = \( \frac{x}{-5} \)
-5 x (3x + 3) = x
(-5 x 3x) + (-5 x 3) = x
-15x - 15 = x
-15x - 15 - x = 0
-15x - x = 15
-16x = 15
x = \( \frac{15}{-16} \)
x = -\(\frac{15}{16}\)