| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.46 |
| Score | 0% | 49% |
Which of the following statements about a parallelogram is not true?
opposite sides and adjacent angles are equal |
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the area of a parallelogram is base x height |
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a parallelogram is a quadrilateral |
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the perimeter of a parallelogram is the sum of the lengths of all sides |
A parallelogram is a quadrilateral with two sets of parallel sides. Opposite sides (a = c, b = d) and angles (red = red, blue = blue) are equal. The area of a parallelogram is base x height and the perimeter is the sum of the lengths of all sides (a + b + c + d).
If the area of this square is 25, what is the length of one of the diagonals?
| 9\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) | |
| 3\( \sqrt{2} \) |
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 = \( \sqrt{a} \) = \( \sqrt{25} \) = 5
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 = 52 + 52
c2 = 50
c = \( \sqrt{50} \) = \( \sqrt{25 x 2} \) = \( \sqrt{25} \) \( \sqrt{2} \)
c = 5\( \sqrt{2} \)
The formula for the area of a circle is which of the following?
c = π d2 |
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c = π d |
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c = π r |
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c = π r2 |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.
If the base of this triangle is 8 and the height is 2, what is the area?
| 38\(\frac{1}{2}\) | |
| 18 | |
| 56 | |
| 8 |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 8 x 2 = \( \frac{16}{2} \) = 8
The endpoints of this line segment are at (-2, 2) and (2, -8). What is the slope of this line?
| -3 | |
| 2 | |
| 2\(\frac{1}{2}\) | |
| -2\(\frac{1}{2}\) |
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, 2) and (2, -8) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-8.0) - (2.0)}{(2) - (-2)} \) = \( \frac{-10}{4} \)