| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.16 |
| Score | 0% | 63% |
What is the area of a circle with a radius of 4?
| 9π | |
| 16π | |
| 49π | |
| 3π |
The formula for area is πr2:
a = πr2
a = π(42)
a = 16π
Which of the following is not required to define the slope-intercept equation for a line?
x-intercept |
|
y-intercept |
|
slope |
|
\({\Delta y \over \Delta x}\) |
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.
What is 4a + 5a?
| 9a | |
| 9a2 | |
| -1 | |
| 20a2 |
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.
4a + 5a = 9a
What is 7a8 - 8a8?
| a816 | |
| -1 | |
| 56a16 | |
| -1a8 |
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.
7a8 - 8a8 = -1a8
The dimensions of this cylinder are height (h) = 3 and radius (r) = 2. What is the surface area?
| 60π | |
| 48π | |
| 20π | |
| 144π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(22) + 2π(2 x 3)
sa = 2π(4) + 2π(6)
sa = (2 x 4)π + (2 x 6)π
sa = 8π + 12π
sa = 20π