| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.08 |
| Score | 0% | 62% |
If the area of this square is 64, what is the length of one of the diagonals?
| 8\( \sqrt{2} \) | |
| 3\( \sqrt{2} \) | |
| 2\( \sqrt{2} \) | |
| 6\( \sqrt{2} \) |
To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:
a = s2
so the length of one side of the square is:
s = \( \sqrt{a} \) = \( \sqrt{64} \) = 8
The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:
c2 = a2 + b2
c2 = 82 + 82
c2 = 128
c = \( \sqrt{128} \) = \( \sqrt{64 x 2} \) = \( \sqrt{64} \) \( \sqrt{2} \)
c = 8\( \sqrt{2} \)
Which of the following expressions contains exactly two terms?
quadratic |
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polynomial |
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binomial |
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monomial |
A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.
When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
supplementary, vertical |
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acute, obtuse |
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obtuse, acute |
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vertical, supplementary |
Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).
Solve for c:
c2 - 15c + 56 = 0
| -8 or -9 | |
| 7 or -4 | |
| 9 or -8 | |
| 7 or 8 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
c2 - 15c + 56 = 0
(c - 7)(c - 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (c - 7) or (c - 8) must equal zero:
If (c - 7) = 0, c must equal 7
If (c - 8) = 0, c must equal 8
So the solution is that c = 7 or 8
Solve -3b + 7b = 9b - 3y + 9 for b in terms of y.
| -1\(\frac{2}{3}\)y - \(\frac{1}{3}\) | |
| 1\(\frac{6}{7}\)y - 1\(\frac{2}{7}\) | |
| -7y + 1 | |
| \(\frac{5}{6}\)y - \(\frac{3}{4}\) |
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.
-3b + 7y = 9b - 3y + 9
-3b = 9b - 3y + 9 - 7y
-3b - 9b = -3y + 9 - 7y
-12b = -10y + 9
b = \( \frac{-10y + 9}{-12} \)
b = \( \frac{-10y}{-12} \) + \( \frac{9}{-12} \)
b = \(\frac{5}{6}\)y - \(\frac{3}{4}\)