| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.21 |
| Score | 0% | 64% |
If the area of this square is 36, what is the length of one of the diagonals?
| 3\( \sqrt{2} \) | |
| 6\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| 9\( \sqrt{2} \) |
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\( \sqrt{2} \)
On this circle, line segment AB is the:
diameter |
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chord |
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circumference |
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radius |
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).
The formula for the area of a circle is which of the following?
a = π d |
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a = π r2 |
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a = π r |
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a = π d2 |
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.
The endpoints of this line segment are at (-2, -4) and (2, -2). What is the slope-intercept equation for this line?
| y = \(\frac{1}{2}\)x - 3 | |
| y = 2\(\frac{1}{2}\)x + 1 | |
| y = 1\(\frac{1}{2}\)x - 2 | |
| y = -1\(\frac{1}{2}\)x - 1 |
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, -4) and (2, -2) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-2.0) - (-4.0)}{(2) - (-2)} \) = \( \frac{2}{4} \)Plugging these values into the slope-intercept equation:
y = \(\frac{1}{2}\)x - 3
Simplify (6a)(3ab) + (2a2)(9b).
| 36a2b | |
| 36ab2 | |
| 2b | |
| 99ab2 |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(6a)(3ab) + (2a2)(9b)
(6 x 3)(a x a x b) + (2 x 9)(a2 x b)
(18)(a1+1 x b) + (18)(a2b)
18a2b + 18a2b
36a2b