| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.10 |
| Score | 0% | 62% |
If angle a = 49° and angle b = 27° what is the length of angle d?
| 131° | |
| 121° | |
| 110° | |
| 143° |
An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:
d° = b° + c°
To find angle c, remember that the sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 49° - 27° = 104°
So, d° = 27° + 104° = 131°
A shortcut to get this answer is to remember that angles around a line add up to 180°:
a° + d° = 180°
d° = 180° - a°
d° = 180° - 49° = 131°
A right angle measures:
90° |
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45° |
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360° |
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180° |
A right angle measures 90 degrees and is the intersection of two perpendicular lines. In diagrams, a right angle is indicated by a small box completing a square with the perpendicular lines.
Breaking apart a quadratic expression into a pair of binomials is called:
factoring |
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normalizing |
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deconstructing |
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squaring |
To factor a quadratic expression, apply the FOIL (First, Outside, Inside, Last) method in reverse.
If the length of AB equals the length of BD, point B __________ this line segment.
trisects |
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midpoints |
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bisects |
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intersects |
A line segment is a portion of a line with a measurable length. The midpoint of a line segment is the point exactly halfway between the endpoints. The midpoint bisects (cuts in half) the line segment.
The endpoints of this line segment are at (-2, -6) and (2, 4). What is the slope-intercept equation for this line?
| y = 2\(\frac{1}{2}\)x - 1 | |
| y = \(\frac{1}{2}\)x + 4 | |
| y = -\(\frac{1}{2}\)x + 2 | |
| y = -2x + 1 |
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 -1. 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, -6) and (2, 4) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(4.0) - (-6.0)}{(2) - (-2)} \) = \( \frac{10}{4} \)Plugging these values into the slope-intercept equation:
y = 2\(\frac{1}{2}\)x - 1