| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.47 |
| Score | 0% | 69% |
What is the area of a circle with a diameter of 6?
| 7π | |
| 9π | |
| 2π | |
| 4π |
The formula for area is πr2. Radius is circle \( \frac{diameter}{2} \):
r = \( \frac{d}{2} \)
r = \( \frac{6}{2} \)
r = 3
a = πr2
a = π(32)
a = 9π
Find the value of a:
8a + x = 3
-2a - x = 9
| \(\frac{16}{43}\) | |
| \(\frac{7}{9}\) | |
| -1\(\frac{5}{8}\) | |
| 2 |
You need to find the value of a so solve the first equation in terms of x:
8a + x = 3
x = 3 - 8a
then substitute the result (3 - 8a) into the second equation:
-2a - 1(3 - 8a) = 9
-2a + (-1 x 3) + (-1 x -8a) = 9
-2a - 3 + 8a = 9
-2a + 8a = 9 + 3
6a = 12
a = \( \frac{12}{6} \)
a = 2
Which of the following is not a part of PEMDAS, the acronym for math order of operations?
addition |
|
division |
|
exponents |
|
pairs |
When solving an equation with two variables, 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.)
If side x = 5cm, side y = 8cm, and side z = 12cm what is the perimeter of this triangle?
| 24cm | |
| 33cm | |
| 30cm | |
| 25cm |
The perimeter of a triangle is the sum of the lengths of its sides:
p = x + y + z
p = 5cm + 8cm + 12cm = 25cm
If angle a = 28° and angle b = 28° what is the length of angle d?
| 122° | |
| 141° | |
| 152° | |
| 144° |
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° - 28° - 28° = 124°
So, d° = 28° + 124° = 152°
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° - 28° = 152°