| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.54 |
| Score | 0% | 71% |
If the area of this square is 4, what is the length of one of the diagonals?
| 6\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| 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 = \( \sqrt{a} \) = \( \sqrt{4} \) = 2
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 = 22 + 22
c2 = 8
c = \( \sqrt{8} \) = \( \sqrt{4 x 2} \) = \( \sqrt{4} \) \( \sqrt{2} \)
c = 2\( \sqrt{2} \)
Which types of triangles will always have at least two sides of equal length?
equilateral and isosceles |
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isosceles and right |
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equilateral, isosceles and right |
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equilateral and right |
An isosceles triangle has two sides of equal length. An equilateral triangle has three sides of equal length. In a right triangle, two sides meet at a right angle.
A coordinate grid is composed of which of the following?
origin |
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y-axis |
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x-axis |
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all of these |
The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.
Simplify (3a)(8ab) - (7a2)(6b).
| 143a2b | |
| 66ab2 | |
| 143ab2 | |
| -18a2b |
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.
(3a)(8ab) - (7a2)(6b)
(3 x 8)(a x a x b) - (7 x 6)(a2 x b)
(24)(a1+1 x b) - (42)(a2b)
24a2b - 42a2b
-18a2b
What is 2a - 5a?
| -3a2 | |
| -3a | |
| 7 | |
| a2 |
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.
2a - 5a = -3a