| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.50 |
| Score | 0% | 70% |
What is the area of a circle with a radius of 3?
| 16π | |
| 64π | |
| 9π | |
| 25π |
The formula for area is πr2:
a = πr2
a = π(32)
a = 9π
Breaking apart a quadratic expression into a pair of binomials is called:
squaring |
|
normalizing |
|
factoring |
|
deconstructing |
To factor a quadratic expression, apply the FOIL (First, Outside, Inside, Last) method in reverse.
The dimensions of this cylinder are height (h) = 5 and radius (r) = 6. What is the volume?
| 32π | |
| 294π | |
| 50π | |
| 180π |
The volume of a cylinder is πr2h:
v = πr2h
v = π(62 x 5)
v = 180π
Solve for x:
x2 + 5x + 6 = -5x - 3
| -1 or -9 | |
| -6 or -7 | |
| 6 or 4 | |
| 5 or -3 |
The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:
x2 + 5x + 6 = -5x - 3
x2 + 5x + 6 + 3 = -5x
x2 + 5x + 5x + 9 = 0
x2 + 10x + 9 = 0
Next, factor the quadratic equation:
x2 + 10x + 9 = 0
(x + 1)(x + 9) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x + 1) or (x + 9) must equal zero:
If (x + 1) = 0, x must equal -1
If (x + 9) = 0, x must equal -9
So the solution is that x = -1 or -9
A right angle measures:
360° |
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90° |
|
45° |
|
180° |
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.