| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.10 |
| Score | 0% | 62% |
If angle a = 40° and angle b = 28° what is the length of angle d?
| 140° | |
| 133° | |
| 118° | |
| 150° |
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° - 40° - 28° = 112°
So, d° = 28° + 112° = 140°
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° - 40° = 140°
A(n) __________ is two expressions separated by an equal sign.
equation |
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formula |
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expression |
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problem |
An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.
Solve for z:
6z - 2 = \( \frac{z}{5} \)
| \(\frac{10}{29}\) | |
| -\(\frac{9}{13}\) | |
| \(\frac{4}{5}\) | |
| -7\(\frac{1}{2}\) |
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 equal sign and the answer on the other.
6z - 2 = \( \frac{z}{5} \)
5 x (6z - 2) = z
(5 x 6z) + (5 x -2) = z
30z - 10 = z
30z - 10 - z = 0
30z - z = 10
29z = 10
z = \( \frac{10}{29} \)
z = \(\frac{10}{29}\)
If angle a = 69° and angle b = 27° what is the length of angle c?
| 84° | |
| 54° | |
| 131° | |
| 126° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 69° - 27° = 84°
If the base of this triangle is 8 and the height is 7, what is the area?
| 28 | |
| 78 | |
| 24 | |
| 17\(\frac{1}{2}\) |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 8 x 7 = \( \frac{56}{2} \) = 28