| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.20 |
| Score | 0% | 64% |
What is the area of a circle with a diameter of 6?
| 8π | |
| 7π | |
| 2π | |
| 9π |
The formula for area is πr2. Radius is circle \( \frac{diameter}{2} \):
r = \( \frac{d}{2} \)
r = \( \frac{6}{2} \)
r = 3
a = πr2
a = π(32)
a = 9π
On this circle, a line segment connecting point A to point D is called:
radius |
|
circumference |
|
chord |
|
diameter |
A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).
If the area of this square is 4, what is the length of one of the diagonals?
| \( \sqrt{2} \) | |
| 9\( \sqrt{2} \) | |
| 2\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) |
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 = \( \sqrt{a} \) = \( \sqrt{4} \) = 2
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 = 22 + 22
c2 = 8
c = \( \sqrt{8} \) = \( \sqrt{4 x 2} \) = \( \sqrt{4} \) \( \sqrt{2} \)
c = 2\( \sqrt{2} \)
The endpoints of this line segment are at (-2, -2) and (2, 6). What is the slope of this line?
| -\(\frac{1}{2}\) | |
| 1\(\frac{1}{2}\) | |
| \(\frac{1}{2}\) | |
| 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, -2) and (2, 6) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(6.0) - (-2.0)}{(2) - (-2)} \) = \( \frac{8}{4} \)A coordinate grid is composed of which of the following?
x-axis |
|
y-axis |
|
origin |
|
all of these |
The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.