| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.20 |
| Score | 0% | 64% |
Solve for z:
z2 + 9z - 6 = 3z + 1
| 5 or 3 | |
| 8 or 1 | |
| 1 or -7 | |
| 5 or -5 |
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 - 6 = 3z + 1
z2 + 9z - 6 - 1 = 3z
z2 + 9z - 3z - 7 = 0
z2 + 6z - 7 = 0
Next, factor the quadratic equation:
z2 + 6z - 7 = 0
(z - 1)(z + 7) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (z - 1) or (z + 7) must equal zero:
If (z - 1) = 0, z must equal 1
If (z + 7) = 0, z must equal -7
So the solution is that z = 1 or -7
What is 2a8 - 4a8?
| 8a8 | |
| -2 | |
| 6a16 | |
| -2a8 |
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.
2a8 - 4a8 = -2a8
If a = c = 3, b = d = 9, and the blue angle = 79°, what is the area of this parallelogram?
| 21 | |
| 27 | |
| 16 | |
| 18 |
The area of a parallelogram is equal to its length x width:
a = l x w
a = a x b
a = 3 x 9
a = 27
A trapezoid is a quadrilateral with one set of __________ sides.
equal length |
|
equal angle |
|
right angle |
|
parallel |
A trapezoid is a quadrilateral with one set of parallel sides.
The dimensions of this cylinder are height (h) = 8 and radius (r) = 8. What is the volume?
| 24π | |
| 512π | |
| 80π | |
| 216π |
The volume of a cylinder is πr2h:
v = πr2h
v = π(82 x 8)
v = 512π