| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.28 |
| Score | 0% | 66% |
The endpoints of this line segment are at (-2, 6) and (2, 0). What is the slope of this line?
| 1 | |
| -1\(\frac{1}{2}\) | |
| 2\(\frac{1}{2}\) | |
| 2 |
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, 0) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(0.0) - (6.0)}{(2) - (-2)} \) = \( \frac{-6}{4} \)When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
obtuse, acute |
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vertical, supplementary |
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supplementary, vertical |
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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).
If AD = 26 and BD = 18, AB = ?
| 14 | |
| 19 | |
| 18 | |
| 8 |
The entire length of this line is represented by AD which is AB + BD:
AD = AB + BD
Solving for AB:AB = AD - BDIf angle a = 31° and angle b = 56° what is the length of angle d?
| 151° | |
| 145° | |
| 153° | |
| 149° |
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° - 31° - 56° = 93°
So, d° = 56° + 93° = 149°
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° - 31° = 149°
A right angle measures:
180° |
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90° |
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360° |
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45° |
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.