| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.32 |
| Score | 0% | 66% |
The dimensions of this cylinder are height (h) = 8 and radius (r) = 5. What is the surface area?
| 24π | |
| 130π | |
| 60π | |
| 144π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(52) + 2π(5 x 8)
sa = 2π(25) + 2π(40)
sa = (2 x 25)π + (2 x 40)π
sa = 50π + 80π
sa = 130π
What is 2a4 + 8a4?
| 16a8 | |
| 10a4 | |
| 16a4 | |
| -6a8 |
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.
2a4 + 8a4 = 10a4
The dimensions of this trapezoid are a = 4, b = 2, c = 6, d = 4, and h = 2. What is the area?
| 6 | |
| 21 | |
| 15 | |
| 30 |
The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:
a = ½(b + d)(h)
a = ½(2 + 4)(2)
a = ½(6)(2)
a = ½(12) = \( \frac{12}{2} \)
a = 6
If a = c = 1, b = d = 3, what is the area of this rectangle?
| 56 | |
| 5 | |
| 3 | |
| 12 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 1 x 3
a = 3
What is 9a - 9a?
| 18a2 | |
| 18 | |
| 81a | |
| 0a |
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.
9a - 9a = 0a