| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.42 |
| Score | 0% | 68% |
What is the area of a circle with a diameter of 8?
| 3π | |
| 4π | |
| 36π | |
| 16π |
The formula for area is πr2. Radius is circle \( \frac{diameter}{2} \):
r = \( \frac{d}{2} \)
r = \( \frac{8}{2} \)
r = 4
a = πr2
a = π(42)
a = 16π
If b = -2 and x = -4, what is the value of 5b(b - x)?
| -20 | |
| 336 | |
| -140 | |
| -24 |
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.)
5b(b - x)
5(-2)(-2 + 4)
5(-2)(2)
(-10)(2)
-20
If side x = 7cm, side y = 15cm, and side z = 15cm what is the perimeter of this triangle?
| 32cm | |
| 39cm | |
| 33cm | |
| 37cm |
The perimeter of a triangle is the sum of the lengths of its sides:
p = x + y + z
p = 7cm + 15cm + 15cm = 37cm
Find the value of c:
-3c + x = 4
5c + 3x = -3
| -1\(\frac{1}{14}\) | |
| -\(\frac{2}{5}\) | |
| \(\frac{2}{7}\) | |
| -1\(\frac{1}{21}\) |
You need to find the value of c so solve the first equation in terms of x:
-3c + x = 4
x = 4 + 3c
then substitute the result (4 - -3c) into the second equation:
5c + 3(4 + 3c) = -3
5c + (3 x 4) + (3 x 3c) = -3
5c + 12 + 9c = -3
5c + 9c = -3 - 12
14c = -15
c = \( \frac{-15}{14} \)
c = -1\(\frac{1}{14}\)
If AD = 12 and BD = 8, AB = ?
| 5 | |
| 17 | |
| 10 | |
| 4 |
The entire length of this line is represented by AD which is AB + BD:
AD = AB + BD
Solving for AB:AB = AD - BD