| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.10 |
| Score | 0% | 62% |
What is the circumference of a circle with a diameter of 12?
| 15π | |
| 9π | |
| 12π | |
| 38π |
The formula for circumference is circle diameter x π:
c = πd
c = 12π
The dimensions of this cylinder are height (h) = 4 and radius (r) = 4. What is the volume?
| 144π | |
| 16π | |
| 32π | |
| 64π |
The volume of a cylinder is πr2h:
v = πr2h
v = π(42 x 4)
v = 64π
Which of the following is not required to define the slope-intercept equation for a line?
slope |
|
x-intercept |
|
y-intercept |
|
\({\Delta y \over \Delta x}\) |
A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.
Solve for x:
x2 - 9x + 8 = 0
| 9 or -9 | |
| -4 or -4 | |
| 1 or 8 | |
| 5 or 4 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
x2 - 9x + 8 = 0
(x - 1)(x - 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x - 1) or (x - 8) must equal zero:
If (x - 1) = 0, x must equal 1
If (x - 8) = 0, x must equal 8
So the solution is that x = 1 or 8
The formula for the area of a circle is which of the following?
a = π r2 |
|
a = π d |
|
a = π d2 |
|
a = π r |
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.