| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.31 |
| Score | 0% | 66% |
The formula for the area of a circle is which of the following?
a = π d2 |
|
a = π r2 |
|
a = π r |
|
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.
If side a = 1, side b = 4, what is the length of the hypotenuse of this right triangle?
| \( \sqrt{2} \) | |
| \( \sqrt{50} \) | |
| \( \sqrt{97} \) | |
| \( \sqrt{17} \) |
According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:
c2 = a2 + b2
c2 = 12 + 42
c2 = 1 + 16
c2 = 17
c = \( \sqrt{17} \)
If angle a = 40° and angle b = 59° what is the length of angle d?
| 140° | |
| 146° | |
| 122° | |
| 127° |
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° - 59° = 81°
So, d° = 59° + 81° = 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°
The formula for volume of a cube in terms of height (h), length (l), and width (w) is which of the following?
h x l x w |
|
2lw x 2wh + 2lh |
|
h2 x l2 x w2 |
|
lw x wh + lh |
A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.
If a = -7 and y = -7, what is the value of -7a(a - y)?
| -50 | |
| -72 | |
| 0 | |
| -48 |
To solve this equation, 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.)
-7a(a - y)
-7(-7)(-7 + 7)
-7(-7)(0)
(49)(0)
0