| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.88 |
| Score | 0% | 58% |
If side a = 5, side b = 4, what is the length of the hypotenuse of this right triangle?
| \( \sqrt{65} \) | |
| \( \sqrt{41} \) | |
| \( \sqrt{10} \) | |
| \( \sqrt{26} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 52 + 42
c2 = 25 + 16
c2 = 41
c = \( \sqrt{41} \)
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 subtract monomials that have the same variable and the same exponent |
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all of these statements are correct |
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you can add monomials that have the same variable and the same exponent |
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.
The dimensions of this trapezoid are a = 5, b = 9, c = 7, d = 7, and h = 4. What is the area?
| 24 | |
| 32 | |
| 35 | |
| 18 |
The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:
a = ½(b + d)(h)
a = ½(9 + 7)(4)
a = ½(16)(4)
a = ½(64) = \( \frac{64}{2} \)
a = 32
If the area of this square is 64, what is the length of one of the diagonals?
| 2\( \sqrt{2} \) | |
| 3\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) |
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\( \sqrt{2} \)
Solve -7a - 8a = 2a - 7z + 3 for a in terms of z.
| \(\frac{9}{14}\)z + \(\frac{1}{7}\) | |
| -3z - 5 | |
| -\(\frac{1}{9}\)z - \(\frac{1}{3}\) | |
| -2z + 6 |
To solve this equation, isolate the variable for which you are solving (a) on one side of the equation and put everything else on the other side.
-7a - 8z = 2a - 7z + 3
-7a = 2a - 7z + 3 + 8z
-7a - 2a = -7z + 3 + 8z
-9a = z + 3
a = \( \frac{z + 3}{-9} \)
a = \( \frac{z}{-9} \) + \( \frac{3}{-9} \)
a = -\(\frac{1}{9}\)z - \(\frac{1}{3}\)