| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.22 |
| Score | 0% | 64% |
If angle a = 20° and angle b = 49° what is the length of angle c?
| 84° | |
| 111° | |
| 119° | |
| 120° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 20° - 49° = 111°
The endpoints of this line segment are at (-2, 5) and (2, 1). What is the slope of this line?
| -2\(\frac{1}{2}\) | |
| -1\(\frac{1}{2}\) | |
| -\(\frac{1}{2}\) | |
| -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, 5) and (2, 1) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(1.0) - (5.0)}{(2) - (-2)} \) = \( \frac{-4}{4} \)Which of the following statements about a triangle is not true?
area = ½bh |
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exterior angle = sum of two adjacent interior angles |
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perimeter = sum of side lengths |
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sum of interior angles = 180° |
A triangle is a three-sided polygon. It has three interior angles that add up to 180° (a + b + c = 180°). An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite (d = b + c). The perimeter of a triangle is equal to the sum of the lengths of its three sides, the height of a triangle is equal to the length from the base to the opposite vertex (angle) and the area equals one-half triangle base x height: a = ½ base x height.
Which of the following is not a part of PEMDAS, the acronym for math order of operations?
division |
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addition |
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pairs |
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exponents |
When solving an equation with two variables, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
Solve for c:
c2 - 14c + 45 = 0
| 3 or -8 | |
| 4 or -1 | |
| -1 or -3 | |
| 5 or 9 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
c2 - 14c + 45 = 0
(c - 5)(c - 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (c - 5) or (c - 9) must equal zero:
If (c - 5) = 0, c must equal 5
If (c - 9) = 0, c must equal 9
So the solution is that c = 5 or 9