| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.55 |
| Score | 0% | 71% |
What is 3a + 4a?
| 7 | |
| 7a | |
| 12a2 | |
| -1 |
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.
3a + 4a = 7a
What is the area of a circle with a radius of 4?
| 25π | |
| 9π | |
| 16π | |
| 8π |
The formula for area is πr2:
a = πr2
a = π(42)
a = 16π
A right angle measures:
45° |
|
360° |
|
90° |
|
180° |
A right angle measures 90 degrees and is the intersection of two perpendicular lines. In diagrams, a right angle is indicated by a small box completing a square with the perpendicular lines.
The endpoints of this line segment are at (-2, 1) and (2, 5). What is the slope-intercept equation for this line?
| y = 2\(\frac{1}{2}\)x + 3 | |
| y = -\(\frac{1}{2}\)x + 0 | |
| y = -1\(\frac{1}{2}\)x + 3 | |
| y = 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 3. 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, 1) and (2, 5) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(5.0) - (1.0)}{(2) - (-2)} \) = \( \frac{4}{4} \)Plugging these values into the slope-intercept equation:
y = x + 3
Order the following types of angle from least number of degrees to most number of degrees.
right, acute, obtuse |
|
right, obtuse, acute |
|
acute, obtuse, right |
|
acute, right, obtuse |
An acute angle measures less than 90°, a right angle measures 90°, and an obtuse angle measures more than 90°.