| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.35 |
| Score | 0% | 67% |
Solve for x:
x2 - 2x - 8 = 0
| -2 or 4 | |
| -1 or -9 | |
| -7 or -9 | |
| 3 or -1 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
x2 - 2x - 8 = 0
(x + 2)(x - 4) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x + 2) or (x - 4) must equal zero:
If (x + 2) = 0, x must equal -2
If (x - 4) = 0, x must equal 4
So the solution is that x = -2 or 4
When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
vertical, supplementary |
|
supplementary, vertical |
|
obtuse, acute |
|
acute, obtuse |
Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).
If side x = 14cm, side y = 5cm, and side z = 12cm what is the perimeter of this triangle?
| 25cm | |
| 36cm | |
| 31cm | |
| 21cm |
The perimeter of a triangle is the sum of the lengths of its sides:
p = x + y + z
p = 14cm + 5cm + 12cm = 31cm
The formula for volume of a cube in terms of height (h), length (l), and width (w) is which of the following?
lw x wh + lh |
|
h x l x w |
|
2lw x 2wh + 2lh |
|
h2 x l2 x w2 |
A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.
Simplify (8a)(6ab) - (5a2)(3b).
| 63a2b | |
| 112ab2 | |
| 112a2b | |
| 33a2b |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(8a)(6ab) - (5a2)(3b)
(8 x 6)(a x a x b) - (5 x 3)(a2 x b)
(48)(a1+1 x b) - (15)(a2b)
48a2b - 15a2b
33a2b