| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.90 |
| Score | 0% | 58% |
What is the circumference of a circle with a diameter of 1?
| 15π | |
| 1π | |
| 14π | |
| 18π |
The formula for circumference is circle diameter x π:
c = πd
c = 1π
Simplify (5a)(7ab) + (5a2)(4b).
| 55a2b | |
| 108a2b | |
| -15a2b | |
| 55ab2 |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(5a)(7ab) + (5a2)(4b)
(5 x 7)(a x a x b) + (5 x 4)(a2 x b)
(35)(a1+1 x b) + (20)(a2b)
35a2b + 20a2b
55a2b
Simplify (y + 7)(y + 2)
| y2 + 5y - 14 | |
| y2 - 5y - 14 | |
| y2 - 9y + 14 | |
| y2 + 9y + 14 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y + 7)(y + 2)
(y x y) + (y x 2) + (7 x y) + (7 x 2)
y2 + 2y + 7y + 14
y2 + 9y + 14
The endpoints of this line segment are at (-2, 2) and (2, -6). What is the slope-intercept equation for this line?
| y = -1\(\frac{1}{2}\)x + 1 | |
| y = x + 2 | |
| y = -2x - 2 | |
| y = 2\(\frac{1}{2}\)x - 3 |
The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is -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 = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-6.0) - (2.0)}{(2) - (-2)} \) = \( \frac{-8}{4} \)Plugging these values into the slope-intercept equation:
y = -2x - 2
On this circle, a line segment connecting point A to point D is called:
diameter |
|
chord |
|
circumference |
|
radius |
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).