| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.61 |
| Score | 0% | 52% |
Solve for x:
x2 + x - 44 = 2x - 2
| -6 or 7 | |
| -4 or -5 | |
| 2 or -3 | |
| 9 or 4 |
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:
x2 + x - 44 = 2x - 2
x2 + x - 44 + 2 = 2x
x2 + x - 2x - 42 = 0
x2 - x - 42 = 0
Next, factor the quadratic equation:
x2 - x - 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
For this diagram, the Pythagorean theorem states that b2 = ?
a2 - c2 |
|
c - a |
|
c2 + a2 |
|
c2 - a2 |
The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c2) is equal to the sum of the two perpendicular sides squared (a2 + b2): c2 = a2 + b2 or, solved for c, \(c = \sqrt{a + b}\)
If the base of this triangle is 2 and the height is 4, what is the area?
| 4 | |
| 25 | |
| 31\(\frac{1}{2}\) | |
| 70 |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 2 x 4 = \( \frac{8}{2} \) = 4
Solve for x:
3x + 8 < \( \frac{x}{-2} \)
| x < -2\(\frac{2}{7}\) | |
| x < 8 | |
| x < -1\(\frac{1}{34}\) | |
| x < 1\(\frac{17}{31}\) |
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.
3x + 8 < \( \frac{x}{-2} \)
-2 x (3x + 8) < x
(-2 x 3x) + (-2 x 8) < x
-6x - 16 < x
-6x - 16 - x < 0
-6x - x < 16
-7x < 16
x < \( \frac{16}{-7} \)
x < -2\(\frac{2}{7}\)
If side a = 4, side b = 9, what is the length of the hypotenuse of this right triangle?
| \( \sqrt{97} \) | |
| \( \sqrt{90} \) | |
| \( \sqrt{5} \) | |
| \( \sqrt{98} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 42 + 92
c2 = 16 + 81
c2 = 97
c = \( \sqrt{97} \)