| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.99 |
| Score | 0% | 60% |
The dimensions of this cylinder are height (h) = 5 and radius (r) = 5. What is the surface area?
| 24π | |
| 240π | |
| 306π | |
| 100π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(52) + 2π(5 x 5)
sa = 2π(25) + 2π(25)
sa = (2 x 25)π + (2 x 25)π
sa = 50π + 50π
sa = 100π
A(n) __________ is to a parallelogram as a square is to a rectangle.
trapezoid |
|
quadrilateral |
|
rhombus |
|
triangle |
A rhombus is a parallelogram with four equal-length sides. A square is a rectangle with four equal-length sides.
If a = c = 2, b = d = 8, what is the area of this rectangle?
| 9 | |
| 16 | |
| 5 | |
| 56 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 2 x 8
a = 16
Solve for a:
a2 - 4a - 45 = 0
| -8 or -9 | |
| -5 or 9 | |
| -7 or -9 | |
| 4 or -8 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
a2 - 4a - 45 = 0
(a + 5)(a - 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (a + 5) or (a - 9) must equal zero:
If (a + 5) = 0, a must equal -5
If (a - 9) = 0, a must equal 9
So the solution is that a = -5 or 9
The dimensions of this cylinder are height (h) = 3 and radius (r) = 7. What is the volume?
| 72π | |
| 405π | |
| 147π | |
| 144π |
The volume of a cylinder is πr2h:
v = πr2h
v = π(72 x 3)
v = 147π