| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.48 |
| Score | 0% | 70% |
If a = 7, b = 6, c = 5, and d = 6, what is the perimeter of this quadrilateral?
| 15 | |
| 28 | |
| 24 | |
| 18 |
Perimeter is equal to the sum of the four sides:
p = a + b + c + d
p = 7 + 6 + 5 + 6
p = 24
Solve for x:
x2 + 11x + 24 = 0
| 1 or -8 | |
| 7 or -2 | |
| -3 or -8 | |
| 4 or 1 |
The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:
x2 + 11x + 24 = 0
(x + 3)(x + 8) = 0
For this expression to be true, the left side of the expression must equal zero. Therefore, either (x + 3) or (x + 8) must equal zero:
If (x + 3) = 0, x must equal -3
If (x + 8) = 0, x must equal -8
So the solution is that x = -3 or -8
If a = c = 5, b = d = 1, and the blue angle = 62°, what is the area of this parallelogram?
| 21 | |
| 9 | |
| 5 | |
| 8 |
The area of a parallelogram is equal to its length x width:
a = l x w
a = a x b
a = 5 x 1
a = 5
If angle a = 58° and angle b = 33° what is the length of angle d?
| 122° | |
| 119° | |
| 127° | |
| 134° |
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° - 58° - 33° = 89°
So, d° = 33° + 89° = 122°
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° - 58° = 122°
What is 3a - 5a?
| -2a | |
| -2 | |
| 8 | |
| 8a2 |
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.
3a - 5a = -2a