| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.56 |
| Score | 0% | 71% |
If the area of this square is 36, what is the length of one of the diagonals?
| 2\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) | |
| 6\( \sqrt{2} \) |
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\( \sqrt{2} \)
If angle a = 24° and angle b = 50° what is the length of angle c?
| 127° | |
| 96° | |
| 106° | |
| 111° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 24° - 50° = 106°
A quadrilateral is a shape with __________ sides.
5 |
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3 |
|
2 |
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4 |
A quadrilateral is a shape with four sides. The perimeter of a quadrilateral is the sum of the lengths of its four sides.
When two lines intersect, adjacent angles are __________ (they add up to 180°) and angles across from either other are __________ (they're equal).
supplementary, vertical |
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obtuse, acute |
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acute, obtuse |
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vertical, supplementary |
Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are supplementary (they add up to 180°) and angles across from either other are vertical (they're equal).
Simplify (y + 7)(y + 7)
| y2 + 14y + 49 | |
| y2 - 49 | |
| 17 | |
| y2 - 14y + 49 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y + 7)(y + 7)
(y x y) + (y x 7) + (7 x y) + (7 x 7)
y2 + 7y + 7y + 49
y2 + 14y + 49