| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.97 |
| Score | 0% | 59% |
The endpoints of this line segment are at (-2, 4) and (2, -8). What is the slope of this line?
| -3 | |
| -2\(\frac{1}{2}\) | |
| 3 | |
| \(\frac{1}{2}\) |
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, 4) and (2, -8) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-8.0) - (4.0)}{(2) - (-2)} \) = \( \frac{-12}{4} \)The dimensions of this cube are height (h) = 2, length (l) = 6, and width (w) = 6. What is the surface area?
| 348 | |
| 120 | |
| 78 | |
| 192 |
The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):
sa = 2lw + 2wh + 2lh
sa = (2 x 6 x 6) + (2 x 6 x 2) + (2 x 6 x 2)
sa = (72) + (24) + (24)
sa = 120
What is 9a - 3a?
| a2 | |
| 6a | |
| 6a2 | |
| 12a2 |
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.
9a - 3a = 6a
If a = 7 and z = -6, what is the value of -5a(a - z)?
| -6 | |
| 468 | |
| -9 | |
| -455 |
To solve this equation, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
-5a(a - z)
-5(7)(7 + 6)
-5(7)(13)
(-35)(13)
-455
Factor y2 + 11y + 28
| (y + 4)(y - 7) | |
| (y + 4)(y + 7) | |
| (y - 4)(y + 7) | |
| (y - 4)(y - 7) |
To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce 28 as well and sum (Inside, Outside) to equal 11. For this problem, those two numbers are 4 and 7. Then, plug these into a set of binomials using the square root of the First variable (y2):
y2 + 11y + 28
y2 + (4 + 7)y + (4 x 7)
(y + 4)(y + 7)