| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
If the area of this square is 4, what is the length of one of the diagonals?
| 4\( \sqrt{2} \) | |
| 2\( \sqrt{2} \) | |
| 8\( \sqrt{2} \) | |
| 5\( \sqrt{2} \) |
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\( \sqrt{2} \)
The dimensions of this trapezoid are a = 5, b = 4, c = 7, d = 2, and h = 4. What is the area?
| 24 | |
| 25\(\frac{1}{2}\) | |
| 12 | |
| 10 |
The area of a trapezoid is one-half the sum of the lengths of the parallel sides multiplied by the height:
a = ½(b + d)(h)
a = ½(4 + 2)(4)
a = ½(6)(4)
a = ½(24) = \( \frac{24}{2} \)
a = 12
If angle a = 41° and angle b = 22° what is the length of angle d?
| 129° | |
| 139° | |
| 150° | |
| 143° |
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° - 41° - 22° = 117°
So, d° = 22° + 117° = 139°
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° - 41° = 139°
The formula for the area of a circle is which of the following?
a = π r |
|
a = π r2 |
|
a = π d2 |
|
a = π d |
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.
The endpoints of this line segment are at (-2, 2) and (2, -8). What is the slope of this line?
| 2\(\frac{1}{2}\) | |
| 1 | |
| -1\(\frac{1}{2}\) | |
| -2\(\frac{1}{2}\) |
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, 2) and (2, -8) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-8.0) - (2.0)}{(2) - (-2)} \) = \( \frac{-10}{4} \)