| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.24 |
| Score | 0% | 65% |
Solve for z:
z2 + 9z + 19 = z + 4
| 1 or -5 | |
| -3 or -5 | |
| -5 or -6 | |
| 3 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:
z2 + 9z + 19 = z + 4
z2 + 9z + 19 - 4 = z
z2 + 9z - z + 15 = 0
z2 + 8z + 15 = 0
Next, factor the quadratic equation:
z2 + 8z + 15 = 0
(z + 3)(z + 5) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z + 3) or (z + 5) must equal zero:
If (z + 3) = 0, z must equal -3
If (z + 5) = 0, z must equal -5
So the solution is that z = -3 or -5
The formula for volume of a cube in terms of height (h), length (l), and width (w) is which of the following?
h2 x l2 x w2 |
|
h x l x w |
|
2lw x 2wh + 2lh |
|
lw x wh + lh |
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.
If angle a = 65° and angle b = 28° what is the length of angle c?
| 92° | |
| 93° | |
| 108° | |
| 87° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 65° - 28° = 87°
What is 7a4 - 8a4?
| 15 | |
| -1 | |
| -1a4 | |
| 15a8 |
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.
7a4 - 8a4 = -1a4
If a = c = 2, b = d = 7, and the blue angle = 57°, what is the area of this parallelogram?
| 12 | |
| 16 | |
| 14 | |
| 10 |
The area of a parallelogram is equal to its length x width:
a = l x w
a = a x b
a = 2 x 7
a = 14