| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.48 |
| Score | 0% | 50% |
Simplify (9a)(8ab) - (6a2)(8b).
| 238ab2 | |
| 24a2b | |
| 120a2b | |
| -24ab2 |
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.
(9a)(8ab) - (6a2)(8b)
(9 x 8)(a x a x b) - (6 x 8)(a2 x b)
(72)(a1+1 x b) - (48)(a2b)
72a2b - 48a2b
24a2b
The formula for the area of a circle is which of the following?
c = π d2 |
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c = π d |
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c = π r2 |
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c = π r |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.
The endpoints of this line segment are at (-2, 7) and (2, -1). What is the slope-intercept equation for this line?
| y = -\(\frac{1}{2}\)x - 1 | |
| y = -\(\frac{1}{2}\)x + 3 | |
| y = 2\(\frac{1}{2}\)x + 2 | |
| y = -2x + 3 |
The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is 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, 7) and (2, -1) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-1.0) - (7.0)}{(2) - (-2)} \) = \( \frac{-8}{4} \)Plugging these values into the slope-intercept equation:
y = -2x + 3
On this circle, line segment CD is the:
circumference |
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radius |
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chord |
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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 formula for the area of a circle is which of the following?
a = π r2 |
|
a = π r |
|
a = π d2 |
|
a = π d |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.