| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.96 |
| Score | 0% | 59% |
Solve 7a - 5a = -7a + 9y - 3 for a in terms of y.
| y - \(\frac{3}{14}\) | |
| -2\(\frac{1}{6}\)y - 1\(\frac{1}{2}\) | |
| -y + 9 | |
| 3\(\frac{1}{2}\)y - 2 |
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 - 5y = -7a + 9y - 3
7a = -7a + 9y - 3 + 5y
7a + 7a = 9y - 3 + 5y
14a = 14y - 3
a = \( \frac{14y - 3}{14} \)
a = \( \frac{14y}{14} \) + \( \frac{-3}{14} \)
a = y - \(\frac{3}{14}\)
Solve for x:
x2 + 13x + 42 = 0
| 1 or -3 | |
| -6 or -7 | |
| 8 or -1 | |
| 7 or -2 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
x2 + 13x + 42 = 0
(x + 6)(x + 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x + 6) or (x + 7) must equal zero:
If (x + 6) = 0, x must equal -6
If (x + 7) = 0, x must equal -7
So the solution is that x = -6 or -7
If AD = 29 and BD = 28, AB = ?
| 9 | |
| 18 | |
| 1 | |
| 20 |
The entire length of this line is represented by AD which is AB + BD:
AD = AB + BD
Solving for AB:AB = AD - BDSimplify (6a)(7ab) - (7a2)(2b).
| 56ab2 | |
| 56a2b | |
| 117a2b | |
| 28a2b |
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.
(6a)(7ab) - (7a2)(2b)
(6 x 7)(a x a x b) - (7 x 2)(a2 x b)
(42)(a1+1 x b) - (14)(a2b)
42a2b - 14a2b
28a2b
The dimensions of this cylinder are height (h) = 3 and radius (r) = 9. What is the volume?
| 144π | |
| 243π | |
| 8π | |
| 4π |
The volume of a cylinder is πr2h:
v = πr2h
v = π(92 x 3)
v = 243π