| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.13 |
| Score | 0% | 63% |
The endpoints of this line segment are at (-2, -2) and (2, 6). What is the slope-intercept equation for this line?
| y = 2x + 2 | |
| y = -3x + 1 | |
| y = 2\(\frac{1}{2}\)x + 4 | |
| y = x + 2 |
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 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, -2) and (2, 6) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(6.0) - (-2.0)}{(2) - (-2)} \) = \( \frac{8}{4} \)Plugging these values into the slope-intercept equation:
y = 2x + 2
If the area of this square is 36, what is the length of one of the diagonals?
| 5\( \sqrt{2} \) | |
| 6\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) | |
| 2\( \sqrt{2} \) |
To find the diagonal we need to know the length of one of the square's sides. We know the area and the area of a square is the length of one side squared:
a = s2
so the length of one side of the square is:
s = \( \sqrt{a} \) = \( \sqrt{36} \) = 6
The Pythagorean theorem defines the square of the hypotenuse (diagonal) of a triangle with a right angle as the sum of the squares of the other two sides:
c2 = a2 + b2
c2 = 62 + 62
c2 = 72
c = \( \sqrt{72} \) = \( \sqrt{36 x 2} \) = \( \sqrt{36} \) \( \sqrt{2} \)
c = 6\( \sqrt{2} \)
What is 7a - 9a?
| -2a | |
| 63a | |
| 63a2 | |
| 16 |
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.
7a - 9a = -2a
This diagram represents two parallel lines with a transversal. If b° = 145, what is the value of w°?
| 165 | |
| 35 | |
| 164 | |
| 152 |
For parallel lines with a transversal, the following relationships apply:
Applying these relationships starting with b° = 145, the value of w° is 35.
A cylinder with a radius (r) and a height (h) has a surface area of:
2(π r2) + 2π rh |
|
π r2h2 |
|
4π r2 |
|
π r2h |
A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r2h and the surface area is 2(π r2) + 2π rh.