| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.64 |
| Score | 0% | 73% |
What is the area of a circle with a radius of 3?
| 8π | |
| 49π | |
| 3π | |
| 9π |
The formula for area is πr2:
a = πr2
a = π(32)
a = 9π
What is 7a + 9a?
| -2a2 | |
| 16a | |
| 16 | |
| 16a2 |
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.
7a + 9a = 16a
If a = c = 9, b = d = 3, what is the area of this rectangle?
| 6 | |
| 9 | |
| 27 | |
| 14 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 9 x 3
a = 27
A cylinder with a radius (r) and a height (h) has a surface area of:
4π r2 |
|
π r2h |
|
2(π r2) + 2π rh |
|
π r2h2 |
A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r2h and the surface area is 2(π r2) + 2π rh.
The formula for the area of a circle is which of the following?
a = π d2 |
|
a = π r2 |
|
a = π r |
|
a = π d |
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.