| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.05 |
| Score | 0% | 61% |
If the area of this square is 49, what is the length of one of the diagonals?
| 9\( \sqrt{2} \) | |
| 7\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) | |
| 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 = \( \sqrt{a} \) = \( \sqrt{49} \) = 7
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 = 72 + 72
c2 = 98
c = \( \sqrt{98} \) = \( \sqrt{49 x 2} \) = \( \sqrt{49} \) \( \sqrt{2} \)
c = 7\( \sqrt{2} \)
If angle a = 40° and angle b = 43° what is the length of angle d?
| 114° | |
| 142° | |
| 118° | |
| 140° |
An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:
d° = b° + c°
To find angle c, remember that the sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 40° - 43° = 97°
So, d° = 43° + 97° = 140°
A shortcut to get this answer is to remember that angles around a line add up to 180°:
a° + d° = 180°
d° = 180° - a°
d° = 180° - 40° = 140°
If the length of AB equals the length of BD, point B __________ this line segment.
midpoints |
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trisects |
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intersects |
|
bisects |
A line segment is a portion of a line with a measurable length. The midpoint of a line segment is the point exactly halfway between the endpoints. The midpoint bisects (cuts in half) the line segment.
If angle a = 29° and angle b = 51° what is the length of angle c?
| 60° | |
| 70° | |
| 105° | |
| 100° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 29° - 51° = 100°
Simplify (2a)(3ab) + (9a2)(4b).
| 65ab2 | |
| 42ab2 | |
| 30a2b | |
| 42a2b |
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.
(2a)(3ab) + (9a2)(4b)
(2 x 3)(a x a x b) + (9 x 4)(a2 x b)
(6)(a1+1 x b) + (36)(a2b)
6a2b + 36a2b
42a2b