| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.57 |
| Score | 0% | 51% |
The dimensions of this cylinder are height (h) = 9 and radius (r) = 6. What is the surface area?
| 180π | |
| 90π | |
| 104π | |
| 40π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(62) + 2π(6 x 9)
sa = 2π(36) + 2π(54)
sa = (2 x 36)π + (2 x 54)π
sa = 72π + 108π
sa = 180π
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.
Find the value of c:
4c + y = -5
-7c - 6y = 9
| \(\frac{24}{31}\) | |
| 3 | |
| -1\(\frac{4}{17}\) | |
| \(\frac{6}{11}\) |
You need to find the value of c so solve the first equation in terms of y:
4c + y = -5
y = -5 - 4c
then substitute the result (-5 - 4c) into the second equation:
-7c - 6(-5 - 4c) = 9
-7c + (-6 x -5) + (-6 x -4c) = 9
-7c + 30 + 24c = 9
-7c + 24c = 9 - 30
17c = -21
c = \( \frac{-21}{17} \)
c = -1\(\frac{4}{17}\)
On this circle, a line segment connecting point A to point D is called:
radius |
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chord |
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circumference |
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diameter |
A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).
The endpoints of this line segment are at (-2, -1) and (2, 9). What is the slope of this line?
| -2\(\frac{1}{2}\) | |
| 2\(\frac{1}{2}\) | |
| 1 | |
| 3 |
The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -1) and (2, 9) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(9.0) - (-1.0)}{(2) - (-2)} \) = \( \frac{10}{4} \)