| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.83 |
| Score | 0% | 57% |
The endpoints of this line segment are at (-2, -9) and (2, 1). What is the slope-intercept equation for this line?
| y = -2\(\frac{1}{2}\)x + 1 | |
| y = 2\(\frac{1}{2}\)x - 4 | |
| y = 1\(\frac{1}{2}\)x + 0 | |
| y = 1\(\frac{1}{2}\)x - 2 |
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 -4. 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, -9) and (2, 1) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(1.0) - (-9.0)}{(2) - (-2)} \) = \( \frac{10}{4} \)Plugging these values into the slope-intercept equation:
y = 2\(\frac{1}{2}\)x - 4
A cylinder with a radius (r) and a height (h) has a surface area of:
2(π r2) + 2π rh |
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π r2h |
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4π r2 |
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π r2h2 |
A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r2h and the surface area is 2(π r2) + 2π rh.
Factor y2 - 4y - 5
| (y + 5)(y + 1) | |
| (y - 5)(y + 1) | |
| (y - 5)(y - 1) | |
| (y + 5)(y - 1) |
To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce -5 as well and sum (Inside, Outside) to equal -4. For this problem, those two numbers are -5 and 1. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 - 4y - 5
y2 + (-5 + 1)y + (-5 x 1)
(y - 5)(y + 1)
What is 9a5 + 2a5?
| 18a10 | |
| 11a5 | |
| a510 | |
| 7a10 |
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.
9a5 + 2a5 = 11a5
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).