| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.82 |
| Score | 0% | 56% |
If the area of this square is 16, what is the length of one of the diagonals?
| 2\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) | |
| 4\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) |
To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:
a = s2
so the length of one side of the square is:
s = \( \sqrt{a} \) = \( \sqrt{16} \) = 4
The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:
c2 = a2 + b2
c2 = 42 + 42
c2 = 32
c = \( \sqrt{32} \) = \( \sqrt{16 x 2} \) = \( \sqrt{16} \) \( \sqrt{2} \)
c = 4\( \sqrt{2} \)
Which of the following statements about a triangle is not true?
exterior angle = sum of two adjacent interior angles |
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sum of interior angles = 180° |
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perimeter = sum of side lengths |
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area = ½bh |
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.
What is 5a8 + 9a8?
| 14a8 | |
| -4 | |
| 45a16 | |
| 45a8 |
To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.
5a8 + 9a8 = 14a8
The endpoints of this line segment are at (-2, 8) and (2, -2). What is the slope of this line?
| -\(\frac{1}{2}\) | |
| -1\(\frac{1}{2}\) | |
| -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, 8) and (2, -2) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-2.0) - (8.0)}{(2) - (-2)} \) = \( \frac{-10}{4} \)Which of the following statements about parallel lines with a transversal is not correct?
same-side interior angles are complementary and equal each other |
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all acute angles equal each other |
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angles in the same position on different parallel lines are called corresponding angles |
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all of the angles formed by a transversal are called interior angles |
Parallel lines are lines that share the same slope (steepness) and therefore never intersect. A transversal occurs when a set of parallel lines are crossed by another line. All of the angles formed by a transversal are called interior angles and angles in the same position on different parallel lines equal each other (a° = w°, b° = x°, c° = z°, d° = y°) and are called corresponding angles. Alternate interior angles are equal (a° = z°, b° = y°, c° = w°, d° = x°) and all acute angles (a° = c° = w° = z°) and all obtuse angles (b° = d° = x° = y°) equal each other. Same-side interior angles are supplementary and add up to 180° (e.g. a° + d° = 180°, d° + c° = 180°).