| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.48 |
| Score | 0% | 50% |
Solve 8c - 4c = -c - 4y - 8 for c in terms of y.
| -\(\frac{1}{4}\)y + \(\frac{5}{8}\) | |
| -\(\frac{1}{4}\)y + \(\frac{9}{16}\) | |
| \(\frac{6}{13}\)y + \(\frac{8}{13}\) | |
| y - \(\frac{8}{9}\) |
To solve this equation, isolate the variable for which you are solving (c) on one side of the equation and put everything else on the other side.
8c - 4y = -c - 4y - 8
8c = -c - 4y - 8 + 4y
8c + c = -4y - 8 + 4y
9c = - 8
c = \( \frac{ - 8}{9} \)
c = \( \frac{}{9} \) + \( \frac{-8}{9} \)
c = y - \(\frac{8}{9}\)
Solve for a:
-8a + 8 < -7 - a
| a < 2\(\frac{1}{7}\) | |
| a < \(\frac{1}{3}\) | |
| a < -1 | |
| a < -1\(\frac{1}{3}\) |
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 < sign and the answer on the other.
-8a + 8 < -7 - a
-8a < -7 - a - 8
-8a + a < -7 - 8
-7a < -15
a < \( \frac{-15}{-7} \)
a < 2\(\frac{1}{7}\)
Solve for x:
7x - 3 = \( \frac{x}{9} \)
| \(\frac{27}{62}\) | |
| -1\(\frac{1}{7}\) | |
| \(\frac{9}{22}\) | |
| -\(\frac{8}{49}\) |
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.
7x - 3 = \( \frac{x}{9} \)
9 x (7x - 3) = x
(9 x 7x) + (9 x -3) = x
63x - 27 = x
63x - 27 - x = 0
63x - x = 27
62x = 27
x = \( \frac{27}{62} \)
x = \(\frac{27}{62}\)
Find the value of a:
6a + z = -2
2a - 9z = 9
| -\(\frac{9}{56}\) | |
| -\(\frac{1}{19}\) | |
| -\(\frac{1}{2}\) | |
| 21 |
You need to find the value of a so solve the first equation in terms of z:
6a + z = -2
z = -2 - 6a
then substitute the result (-2 - 6a) into the second equation:
2a - 9(-2 - 6a) = 9
2a + (-9 x -2) + (-9 x -6a) = 9
2a + 18 + 54a = 9
2a + 54a = 9 - 18
56a = -9
a = \( \frac{-9}{56} \)
a = -\(\frac{9}{56}\)
If a = -4 and x = 1, what is the value of 2a(a - x)?
| 40 | |
| 0 | |
| 192 | |
| -28 |
To solve this equation, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
2a(a - x)
2(-4)(-4 - 1)
2(-4)(-5)
(-8)(-5)
40