| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.94 |
| Score | 0% | 59% |
The dimensions of this cylinder are height (h) = 4 and radius (r) = 5. What is the surface area?
| 104π | |
| 234π | |
| 108π | |
| 90π |
The surface area of a cylinder is 2πr2 + 2πrh:
sa = 2πr2 + 2πrh
sa = 2π(52) + 2π(5 x 4)
sa = 2π(25) + 2π(20)
sa = (2 x 25)π + (2 x 20)π
sa = 50π + 40π
sa = 90π
If the base of this triangle is 4 and the height is 5, what is the area?
| 10 | |
| 36 | |
| 56 | |
| 30 |
The area of a triangle is equal to ½ base x height:
a = ½bh
a = ½ x 4 x 5 = \( \frac{20}{2} \) = 10
If a = -2 and x = 2, what is the value of -5a(a - x)?
| -40 | |
| -280 | |
| 100 | |
| -360 |
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.)
-5a(a - x)
-5(-2)(-2 - 2)
-5(-2)(-4)
(10)(-4)
-40
Simplify (y + 3)(y - 9)
| y2 + 12y + 27 | |
| y2 - 12y + 27 | |
| y2 - 6y - 27 | |
| y2 + 6y - 27 |
To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses:
(y + 3)(y - 9)
(y x y) + (y x -9) + (3 x y) + (3 x -9)
y2 - 9y + 3y - 27
y2 - 6y - 27
If angle a = 60° and angle b = 68° what is the length of angle d?
| 120° | |
| 129° | |
| 141° | |
| 138° |
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° - 60° - 68° = 52°
So, d° = 68° + 52° = 120°
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° - 60° = 120°