| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.37 |
| Score | 0% | 67% |
The dimensions of this cylinder are height (h) = 8 and radius (r) = 5. What is the surface area?
| 130π | |
| 224π | |
| 64π | |
| 196π |
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
A right angle measures:
90° |
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360° |
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180° |
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45° |
A right angle measures 90 degrees and is the intersection of two perpendicular lines. In diagrams, a right angle is indicated by a small box completing a square with the perpendicular lines.
Factor y2 + 2y - 48
| (y + 6)(y + 8) | |
| (y - 6)(y - 8) | |
| (y - 6)(y + 8) | |
| (y + 6)(y - 8) |
To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce -48 as well and sum (Inside, Outside) to equal 2. For this problem, those two numbers are -6 and 8. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 + 2y - 48
y2 + (-6 + 8)y + (-6 x 8)
(y - 6)(y + 8)
If a = c = 9, b = d = 1, what is the area of this rectangle?
| 42 | |
| 9 | |
| 21 | |
| 1 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 9 x 1
a = 9
Which of the following is not true about both rectangles and squares?
the lengths of all sides are equal |
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all interior angles are right angles |
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the area is length x width |
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the perimeter is the sum of the lengths of all four sides |
A rectangle is a parallelogram containing four right angles. Opposite sides (a = c, b = d) are equal and the perimeter is the sum of the lengths of all sides (a + b + c + d) or, comonly, 2 x length x width. The area of a rectangle is length x width. A square is a rectangle with four equal length sides. The perimeter of a square is 4 x length of one side (4s) and the area is the length of one side squared (s2).