| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.18 |
| Score | 0% | 64% |
A right angle measures:
360° |
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180° |
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90° |
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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.
What is the circumference of a circle with a radius of 4?
| 4π | |
| 36π | |
| 8π | |
| 24π |
The formula for circumference is circle diameter x π. Circle diameter is 2 x radius:
c = πd
c = π(2 * r)
c = π(2 * 4)
c = 8π
For this diagram, the Pythagorean theorem states that b2 = ?
c - a |
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a2 - c2 |
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c2 + a2 |
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c2 - a2 |
The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c2) is equal to the sum of the two perpendicular sides squared (a2 + b2): c2 = a2 + b2 or, solved for c, \(c = \sqrt{a + b}\)
Solve -8b - 4b = -6b + 5x - 6 for b in terms of x.
| -\(\frac{7}{9}\)x - \(\frac{5}{9}\) | |
| \(\frac{1}{2}\)x - \(\frac{1}{6}\) | |
| -4\(\frac{1}{2}\)x + 3 | |
| -1\(\frac{1}{3}\)x + 2\(\frac{1}{3}\) |
To solve this equation, isolate the variable for which you are solving (b) on one side of the equation and put everything else on the other side.
-8b - 4x = -6b + 5x - 6
-8b = -6b + 5x - 6 + 4x
-8b + 6b = 5x - 6 + 4x
-2b = 9x - 6
b = \( \frac{9x - 6}{-2} \)
b = \( \frac{9x}{-2} \) + \( \frac{-6}{-2} \)
b = -4\(\frac{1}{2}\)x + 3
A(n) __________ is two expressions separated by an equal sign.
problem |
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expression |
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formula |
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equation |
An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.