| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.81 |
| Score | 0% | 56% |
Solve 7b - 3b = b + 8y + 8 for b in terms of y.
| 1\(\frac{5}{6}\)y + 1\(\frac{1}{3}\) | |
| y - \(\frac{2}{3}\) | |
| -7y + 4 | |
| -\(\frac{3}{4}\)y - \(\frac{7}{12}\) |
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.
7b - 3y = b + 8y + 8
7b = b + 8y + 8 + 3y
7b - b = 8y + 8 + 3y
6b = 11y + 8
b = \( \frac{11y + 8}{6} \)
b = \( \frac{11y}{6} \) + \( \frac{8}{6} \)
b = 1\(\frac{5}{6}\)y + 1\(\frac{1}{3}\)
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.
Simplify (8a)(3ab) - (5a2)(4b).
| -4ab2 | |
| 99a2b | |
| 4a2b | |
| 44a2b |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(8a)(3ab) - (5a2)(4b)
(8 x 3)(a x a x b) - (5 x 4)(a2 x b)
(24)(a1+1 x b) - (20)(a2b)
24a2b - 20a2b
4a2b
Solve for c:
-2c - 7 = \( \frac{c}{1} \)
| \(\frac{6}{11}\) | |
| -2\(\frac{1}{3}\) | |
| 1 | |
| 1\(\frac{7}{9}\) |
To solve this equation, 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.
-2c - 7 = \( \frac{c}{1} \)
1 x (-2c - 7) = c
(1 x -2c) + (1 x -7) = c
-2c - 7 = c
-2c - 7 - c = 0
-2c - c = 7
-3c = 7
c = \( \frac{7}{-3} \)
c = -2\(\frac{1}{3}\)
The formula for volume of a cube in terms of height (h), length (l), and width (w) is which of the following?
lw x wh + lh |
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h2 x l2 x w2 |
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h x l x w |
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2lw x 2wh + 2lh |
A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.