| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.85 |
| Score | 0% | 57% |
What is the area of a circle with a diameter of 6?
| 8π | |
| 9π | |
| 7π | |
| 64π |
The formula for area is πr2. Radius is circle \( \frac{diameter}{2} \):
r = \( \frac{d}{2} \)
r = \( \frac{6}{2} \)
r = 3
a = πr2
a = π(32)
a = 9π
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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obtuse, acute |
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supplementary, vertical |
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).
On this circle, a line segment connecting point A to point D is called:
circumference |
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chord |
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diameter |
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radius |
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).
Solve for y:
7y - 3 < 2 - y
| y < \(\frac{5}{8}\) | |
| y < 3\(\frac{1}{2}\) | |
| y < -4\(\frac{1}{2}\) | |
| y < -1\(\frac{3}{4}\) |
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 < sign and the answer on the other.
7y - 3 < 2 - y
7y < 2 - y + 3
7y + y < 2 + 3
8y < 5
y < \( \frac{5}{8} \)
y < \(\frac{5}{8}\)
Factor y2 - y - 56
| (y + 8)(y - 7) | |
| (y - 8)(y + 7) | |
| (y + 8)(y + 7) | |
| (y - 8)(y - 7) |
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 -56 as well and sum (Inside, Outside) to equal -1. For this problem, those two numbers are -8 and 7. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 - y - 56
y2 + (-8 + 7)y + (-8 x 7)
(y - 8)(y + 7)