| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.89 |
| Score | 0% | 58% |
If the area of this square is 64, what is the length of one of the diagonals?
| 8\( \sqrt{2} \) | |
| 4\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| \( \sqrt{2} \) |
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 = \( \sqrt{a} \) = \( \sqrt{64} \) = 8
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 = 82 + 82
c2 = 128
c = \( \sqrt{128} \) = \( \sqrt{64 x 2} \) = \( \sqrt{64} \) \( \sqrt{2} \)
c = 8\( \sqrt{2} \)
Which of the following expressions contains exactly two terms?
binomial |
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monomial |
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quadratic |
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polynomial |
A monomial contains one term, a binomial contains two terms, and a polynomial contains more than two terms.
On this circle, line segment CD is the:
chord |
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diameter |
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radius |
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circumference |
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).
Solve for x:
x2 + 4x + 3 = -x - 1
| 9 or -5 | |
| 5 or -8 | |
| 5 or 3 | |
| -1 or -4 |
The first step to solve a quadratic expression that's not set to zero is to solve the equation so that it is set to zero:
x2 + 4x + 3 = -x - 1
x2 + 4x + 3 + 1 = -x
x2 + 4x + x + 4 = 0
x2 + 5x + 4 = 0
Next, factor the quadratic equation:
x2 + 5x + 4 = 0
(x + 1)(x + 4) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x + 1) or (x + 4) must equal zero:
If (x + 1) = 0, x must equal -1
If (x + 4) = 0, x must equal -4
So the solution is that x = -1 or -4
The endpoints of this line segment are at (-2, -6) and (2, 6). What is the slope-intercept equation for this line?
| y = 3x + 0 | |
| y = -x - 3 | |
| y = -3x + 2 | |
| y = 2\(\frac{1}{2}\)x + 0 |
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 0. 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, -6) and (2, 6) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(6.0) - (-6.0)}{(2) - (-2)} \) = \( \frac{12}{4} \)Plugging these values into the slope-intercept equation:
y = 3x + 0