| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.54 |
| Score | 0% | 51% |
The endpoints of this line segment are at (-2, 3) and (2, -5). What is the slope-intercept equation for this line?
| y = -2x - 1 | |
| y = -3x - 2 | |
| y = 2\(\frac{1}{2}\)x + 4 | |
| y = 2\(\frac{1}{2}\)x + 3 |
The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is -1. 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, 3) and (2, -5) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-5.0) - (3.0)}{(2) - (-2)} \) = \( \frac{-8}{4} \)Plugging these values into the slope-intercept equation:
y = -2x - 1
The dimensions of this trapezoid are a = 5, b = 7, c = 6, d = 5, and h = 4. What is the area?
| 22 | |
| 24 | |
| 9 | |
| 36 |
The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:
a = ½(b + d)(h)
a = ½(7 + 5)(4)
a = ½(12)(4)
a = ½(48) = \( \frac{48}{2} \)
a = 24
Find the value of b:
-5b + x = -6
9b - 3x = 5
| -\(\frac{17}{25}\) | |
| 1\(\frac{3}{13}\) | |
| 2\(\frac{1}{6}\) | |
| -\(\frac{26}{57}\) |
You need to find the value of b so solve the first equation in terms of x:
-5b + x = -6
x = -6 + 5b
then substitute the result (-6 - -5b) into the second equation:
9b - 3(-6 + 5b) = 5
9b + (-3 x -6) + (-3 x 5b) = 5
9b + 18 - 15b = 5
9b - 15b = 5 - 18
-6b = -13
b = \( \frac{-13}{-6} \)
b = 2\(\frac{1}{6}\)
The endpoints of this line segment are at (-2, 0) and (2, -4). What is the slope of this line?
| -1\(\frac{1}{2}\) | |
| -3 | |
| -2 | |
| -1 |
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, 0) and (2, -4) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-4.0) - (0.0)}{(2) - (-2)} \) = \( \frac{-4}{4} \)What is 2a6 - 5a6?
| 7 | |
| 10a6 | |
| -3a6 | |
| 7a12 |
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.
2a6 - 5a6 = -3a6