| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.20 |
| Score | 0% | 64% |
Solve for c:
c2 + 2c - 3 = 0
| -1 or -6 | |
| 1 or -3 | |
| 4 or -3 | |
| -5 or -9 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
c2 + 2c - 3 = 0
(c - 1)(c + 3) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (c - 1) or (c + 3) must equal zero:
If (c - 1) = 0, c must equal 1
If (c + 3) = 0, c must equal -3
So the solution is that c = 1 or -3
What is 2a + 3a?
| 5a | |
| a2 | |
| -a2 | |
| 5a2 |
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.
2a + 3a = 5a
If AD = 23 and BD = 18, AB = ?
| 11 | |
| 18 | |
| 12 | |
| 5 |
The entire length of this line is represented by AD which is AB + BD:
AD = AB + BD
Solving for AB:AB = AD - BDSolve for c:
c2 - 9c + 24 = c + 3
| 5 or -8 | |
| 9 or -8 | |
| 3 or 7 | |
| 8 or 7 |
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:
c2 - 9c + 24 = c + 3
c2 - 9c + 24 - 3 = c
c2 - 9c - c + 21 = 0
c2 - 10c + 21 = 0
Next, factor the quadratic equation:
c2 - 10c + 21 = 0
(c - 3)(c - 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (c - 3) or (c - 7) must equal zero:
If (c - 3) = 0, c must equal 3
If (c - 7) = 0, c must equal 7
So the solution is that c = 3 or 7
Which types of triangles will always have at least two sides of equal length?
equilateral and right |
|
isosceles and right |
|
equilateral, isosceles and right |
|
equilateral and isosceles |
An isosceles triangle has two sides of equal length. An equilateral triangle has three sides of equal length. In a right triangle, two sides meet at a right angle.