| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.52 |
| Score | 0% | 70% |
What is the area of a circle with a diameter of 6?
| 6π | |
| 9π | |
| 16π | |
| 36π |
The formula for area is πr2. Radius is circle \( \frac{diameter}{2} \):
r = \( \frac{d}{2} \)
r = \( \frac{6}{2} \)
r = 3
a = πr2
a = π(32)
a = 9π
Which of the following statements about math operations is incorrect?
you can multiply monomials that have different variables and different exponents |
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you can add monomials that have the same variable and the same exponent |
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you can subtract monomials that have the same variable and the same exponent |
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all of these statements are correct |
You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a2 - a2 = 3a2 but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.
If angle a = 30° and angle b = 69° what is the length of angle c?
| 68° | |
| 97° | |
| 81° | |
| 98° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 30° - 69° = 81°
A right angle measures:
90° |
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45° |
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360° |
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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.
Factor y2 - y - 6
| (y - 3)(y + 2) | |
| (y + 3)(y + 2) | |
| (y + 3)(y - 2) | |
| (y - 3)(y - 2) |
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 -6 as well and sum (Inside, Outside) to equal -1. For this problem, those two numbers are -3 and 2. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 - y - 6
y2 + (-3 + 2)y + (-3 x 2)
(y - 3)(y + 2)