| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
If angle a = 28° and angle b = 54° what is the length of angle c?
| 86° | |
| 98° | |
| 113° | |
| 82° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 28° - 54° = 98°
Solve -9a - 3a = -a - 8z + 4 for a in terms of z.
| \(\frac{7}{11}\)z - \(\frac{2}{11}\) | |
| \(\frac{5}{8}\)z - \(\frac{1}{2}\) | |
| 2z + 7 | |
| \(\frac{5}{6}\)z - \(\frac{1}{2}\) |
To solve this equation, isolate the variable for which you are solving (a) on one side of the equation and put everything else on the other side.
-9a - 3z = -a - 8z + 4
-9a = -a - 8z + 4 + 3z
-9a + a = -8z + 4 + 3z
-8a = -5z + 4
a = \( \frac{-5z + 4}{-8} \)
a = \( \frac{-5z}{-8} \) + \( \frac{4}{-8} \)
a = \(\frac{5}{8}\)z - \(\frac{1}{2}\)
The endpoints of this line segment are at (-2, -4) and (2, 4). What is the slope-intercept equation for this line?
| y = 2x + 0 | |
| y = x + 0 | |
| y = -2\(\frac{1}{2}\)x - 1 | |
| y = -2x - 1 |
The slope-intercept equation for a line is y = mx + b where m is the slope and b is the y-intercept of the line. From the graph, you can see that the y-intercept (the y-value from the point where the line crosses the y-axis) is 0. The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, -4) and (2, 4) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(4.0) - (-4.0)}{(2) - (-2)} \) = \( \frac{8}{4} \)Plugging these values into the slope-intercept equation:
y = 2x + 0
Simplify (9a)(7ab) - (7a2)(5b).
| -28ab2 | |
| 192ab2 | |
| 98a2b | |
| 28a2b |
To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.
(9a)(7ab) - (7a2)(5b)
(9 x 7)(a x a x b) - (7 x 5)(a2 x b)
(63)(a1+1 x b) - (35)(a2b)
63a2b - 35a2b
28a2b
If a = 5, b = 2, c = 4, and d = 1, what is the perimeter of this quadrilateral?
| 22 | |
| 23 | |
| 12 | |
| 20 |
Perimeter is equal to the sum of the four sides:
p = a + b + c + d
p = 5 + 2 + 4 + 1
p = 12