| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
The endpoints of this line segment are at (-2, -1) and (2, -3). What is the slope-intercept equation for this line?
| y = -\(\frac{1}{2}\)x + 2 | |
| y = -2x + 2 | |
| y = 3x - 2 | |
| y = -\(\frac{1}{2}\)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, -1) and (2, -3) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-3.0) - (-1.0)}{(2) - (-2)} \) = \( \frac{-2}{4} \)Plugging these values into the slope-intercept equation:
y = -\(\frac{1}{2}\)x - 2
What is 8a - 7a?
| a2 | |
| 56a2 | |
| 56a | |
| 1a |
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.
8a - 7a = 1a
Solve for b:
b2 - 3b - 10 = 0
| -8 or -9 | |
| -2 or 5 | |
| 1 or -1 | |
| 7 or -9 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
b2 - 3b - 10 = 0
(b + 2)(b - 5) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (b + 2) or (b - 5) must equal zero:
If (b + 2) = 0, b must equal -2
If (b - 5) = 0, b must equal 5
So the solution is that b = -2 or 5
On this circle, line segment AB is the:
radius |
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circumference |
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chord |
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diameter |
A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).
For this diagram, the Pythagorean theorem states that b2 = ?
c2 + a2 |
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c - a |
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c2 - a2 |
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a2 - c2 |
The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c2) is equal to the sum of the two perpendicular sides squared (a2 + b2): c2 = a2 + b2 or, solved for c, \(c = \sqrt{a + b}\)