| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.96 |
| Score | 0% | 59% |
If the base of this triangle is 8 and the height is 9, what is the area?
| 75 | |
| 55 | |
| 60 | |
| 36 |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 8 x 9 = \( \frac{72}{2} \) = 36
The endpoints of this line segment are at (-2, -2) and (2, 6). What is the slope of this line?
| -2 | |
| 2 | |
| 3 | |
| 1\(\frac{1}{2}\) |
The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -2) and (2, 6) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(6.0) - (-2.0)}{(2) - (-2)} \) = \( \frac{8}{4} \)What is the circumference of a circle with a diameter of 16?
| 12π | |
| 16π | |
| 13π | |
| 4π |
The formula for circumference is circle diameter x π:
c = πd
c = 16π
Simplify (y - 4)(y + 8)
| y2 + 12y + 32 | |
| y2 + 4y - 32 | |
| y2 - 4y - 32 | |
| y2 - 12y + 32 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y - 4)(y + 8)
(y x y) + (y x 8) + (-4 x y) + (-4 x 8)
y2 + 8y - 4y - 32
y2 + 4y - 32
Solve for z:
z2 - 2z - 8 = 0
| 7 or 5 | |
| 8 or -5 | |
| -2 or 4 | |
| 4 or -9 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
z2 - 2z - 8 = 0
(z + 2)(z - 4) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z + 2) or (z - 4) must equal zero:
If (z + 2) = 0, z must equal -2
If (z - 4) = 0, z must equal 4
So the solution is that z = -2 or 4