| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.01 |
| Score | 0% | 60% |
What is 6a7 - 7a7?
| 42a14 | |
| -1 | |
| 13a14 | |
| -1a7 |
To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.
6a7 - 7a7 = -1a7
Solve for z:
-2z - 8 = 5 - 4z
| 1\(\frac{2}{7}\) | |
| \(\frac{2}{3}\) | |
| -\(\frac{1}{2}\) | |
| 6\(\frac{1}{2}\) |
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.
-2z - 8 = 5 - 4z
-2z = 5 - 4z + 8
-2z + 4z = 5 + 8
2z = 13
z = \( \frac{13}{2} \)
z = 6\(\frac{1}{2}\)
Solve for c:
3c - 4 > \( \frac{c}{-1} \)
| c > 1 | |
| c > -\(\frac{9}{53}\) | |
| c > \(\frac{1}{3}\) | |
| c > -4\(\frac{4}{9}\) |
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 > sign and the answer on the other.
3c - 4 > \( \frac{c}{-1} \)
-1 x (3c - 4) > c
(-1 x 3c) + (-1 x -4) > c
-3c + 4 > c
-3c + 4 - c > 0
-3c - c > -4
-4c > -4
c > \( \frac{-4}{-4} \)
c > 1
If BD = 7 and AD = 17, AB = ?
| 10 | |
| 14 | |
| 18 | |
| 9 |
The entire length of this line is represented by AD which is AB + BD:
AD = AB + BD
Solving for AB:AB = AD - BDSolve for z:
z2 + 3z - 37 = 2z + 5
| 9 or -3 | |
| 6 or -7 | |
| -3 or -8 | |
| -2 or -9 |
The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:
z2 + 3z - 37 = 2z + 5
z2 + 3z - 37 - 5 = 2z
z2 + 3z - 2z - 42 = 0
z2 + z - 42 = 0
Next, factor the quadratic equation:
z2 + z - 42 = 0
(z - 6)(z + 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z - 6) or (z + 7) must equal zero:
If (z - 6) = 0, z must equal 6
If (z + 7) = 0, z must equal -7
So the solution is that z = 6 or -7