| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.37 |
| Score | 0% | 67% |
The dimensions of this cube are height (h) = 7, length (l) = 8, and width (w) = 8. What is the surface area?
| 40 | |
| 314 | |
| 52 | |
| 352 |
The surface area of a cube is (2 x length x width) + (2 x width x height) + (2 x length x height):
sa = 2lw + 2wh + 2lh
sa = (2 x 8 x 8) + (2 x 8 x 7) + (2 x 8 x 7)
sa = (128) + (112) + (112)
sa = 352
What is the circumference of a circle with a diameter of 18?
| 38π | |
| 13π | |
| 8π | |
| 18π |
The formula for circumference is circle diameter x π:
c = πd
c = 18π
If angle a = 68° and angle b = 57° what is the length of angle d?
| 112° | |
| 155° | |
| 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° - 68° - 57° = 55°
So, d° = 57° + 55° = 112°
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° - 68° = 112°
What is 5a + 3a?
| 8a2 | |
| 8a | |
| 15a | |
| 15a2 |
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.
5a + 3a = 8a
What is 8a7 + 4a7?
| 4a14 | |
| 12 | |
| 4 | |
| 12a7 |
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.
8a7 + 4a7 = 12a7