| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.88 |
| Score | 0% | 58% |
If angle a = 48° and angle b = 67° what is the length of angle c?
| 73° | |
| 80° | |
| 65° | |
| 85° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 48° - 67° = 65°
Solve 6c + 9c = 7c + 9x - 8 for c in terms of x.
| -1\(\frac{1}{3}\)x + 2\(\frac{1}{3}\) | |
| -\(\frac{8}{9}\)x + \(\frac{4}{9}\) | |
| -6x + 4 | |
| x + 8 |
To solve this equation, isolate the variable for which you are solving (c) on one side of the equation and put everything else on the other side.
6c + 9x = 7c + 9x - 8
6c = 7c + 9x - 8 - 9x
6c - 7c = 9x - 8 - 9x
-c = - 8
c = \( \frac{ - 8}{-1} \)
c = \( \frac{}{-1} \) + \( \frac{-8}{-1} \)
c = x + 8
Find the value of b:
-4b + z = -5
-6b + 5z = 7
| -1\(\frac{8}{47}\) | |
| -\(\frac{1}{33}\) | |
| 2\(\frac{2}{7}\) |
You need to find the value of b so solve the first equation in terms of z:
-4b + z = -5
z = -5 + 4b
then substitute the result (-5 - -4b) into the second equation:
-6b + 5(-5 + 4b) = 7
-6b + (5 x -5) + (5 x 4b) = 7
-6b - 25 + 20b = 7
-6b + 20b = 7 + 25
14b = 32
b = \( \frac{32}{14} \)
b = 2\(\frac{2}{7}\)
Simplify (y + 9)(y - 7)
| y2 - 16y + 63 | |
| y2 - 2y - 63 | |
| y2 + 2y - 63 | |
| y2 + 16y + 63 |
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 + 9)(y - 7)
(y x y) + (y x -7) + (9 x y) + (9 x -7)
y2 - 7y + 9y - 63
y2 + 2y - 63
Order the following types of angle from least number of degrees to most number of degrees.
acute, right, obtuse |
|
right, obtuse, acute |
|
right, acute, obtuse |
|
acute, obtuse, right |
An acute angle measures less than 90°, a right angle measures 90°, and an obtuse angle measures more than 90°.