| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.53 |
| Score | 0% | 71% |
The dimensions of this cube are height (h) = 9, length (l) = 3, and width (w) = 6. What is the surface area?
| 378 | |
| 172 | |
| 198 | |
| 48 |
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 3 x 6) + (2 x 6 x 9) + (2 x 3 x 9)
sa = (36) + (108) + (54)
sa = 198
What is 7a - 2a?
| a2 | |
| 9a2 | |
| 14a2 | |
| 5a |
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.
7a - 2a = 5a
If a = c = 6, b = d = 8, what is the area of this rectangle?
| 48 | |
| 8 | |
| 18 | |
| 12 |
The area of a rectangle is equal to its length x width:
a = l x w
a = a x b
a = 6 x 8
a = 48
If a = 9, b = 4, c = 4, and d = 5, what is the perimeter of this quadrilateral?
| 14 | |
| 15 | |
| 22 | |
| 17 |
Perimeter is equal to the sum of the four sides:
p = a + b + c + d
p = 9 + 4 + 4 + 5
p = 22
If angle a = 61° and angle b = 47° what is the length of angle d?
| 145° | |
| 147° | |
| 119° | |
| 118° |
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° - 61° - 47° = 72°
So, d° = 47° + 72° = 119°
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° - 61° = 119°