| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.52 |
| Score | 0% | 50% |
If angle a = 37° and angle b = 32° what is the length of angle d?
| 143° | |
| 154° | |
| 146° | |
| 145° |
An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:
d° = b° + c°
To find angle c, remember that the sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 37° - 32° = 111°
So, d° = 32° + 111° = 143°
A shortcut to get this answer is to remember that angles around a line add up to 180°:
a° + d° = 180°
d° = 180° - a°
d° = 180° - 37° = 143°
The endpoints of this line segment are at (-2, -1) and (2, 3). What is the slope-intercept equation for this line?
| y = -3x - 3 | |
| y = 2\(\frac{1}{2}\)x - 3 | |
| y = x + 1 | |
| y = -x + 4 |
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, -1) and (2, 3) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(3.0) - (-1.0)}{(2) - (-2)} \) = \( \frac{4}{4} \)Plugging these values into the slope-intercept equation:
y = x + 1
The formula for the area of a circle is which of the following?
c = π d |
|
c = π r |
|
c = π d2 |
|
c = π r2 |
The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)2 : a = π r2.
What is 2a - 8a?
| -6a | |
| a2 | |
| 16a2 | |
| 16a |
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.
2a - 8a = -6a
The dimensions of this cube are height (h) = 9, length (l) = 4, and width (w) = 5. What is the surface area?
| 202 | |
| 192 | |
| 48 | |
| 38 |
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 4 x 5) + (2 x 5 x 9) + (2 x 4 x 9)
sa = (40) + (90) + (72)
sa = 202