| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.84 |
| Score | 0% | 77% |
If the area of this square is 25, what is the length of one of the diagonals?
| 6\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) | |
| 9\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) |
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 = \( \sqrt{a} \) = \( \sqrt{25} \) = 5
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 = 52 + 52
c2 = 50
c = \( \sqrt{50} \) = \( \sqrt{25 x 2} \) = \( \sqrt{25} \) \( \sqrt{2} \)
c = 5\( \sqrt{2} \)
The formula for the area of a circle is which of the following?
a = π r |
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a = π d2 |
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a = π d |
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a = 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.
Solve for c:
5c - 1 < 8 + c
| c < \(\frac{3}{5}\) | |
| c < 2\(\frac{1}{4}\) | |
| c < 1\(\frac{1}{4}\) | |
| c < 3 |
To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the < sign and the answer on the other.
5c - 1 < 8 + c
5c < 8 + c + 1
5c - c < 8 + 1
4c < 9
c < \( \frac{9}{4} \)
c < 2\(\frac{1}{4}\)
Which of the following is not a part of PEMDAS, the acronym for math order of operations?
addition |
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division |
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pairs |
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exponents |
When solving an equation with two variables, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
A quadrilateral is a shape with __________ sides.
2 |
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4 |
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5 |
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3 |
A quadrilateral is a shape with four sides. The perimeter of a quadrilateral is the sum of the lengths of its four sides.