| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
Which of the following statements about math operations is incorrect?
all of these statements are correct |
|
you can multiply monomials that have different variables and different exponents |
|
you can subtract monomials that have the same variable and the same exponent |
|
you can add monomials that have the same variable and the same exponent |
You can only add or subtract monomials that have the same variable and the same exponent. For example, 2a + 4a = 6a and 4a2 - a2 = 3a2 but 2a + 4b and 7a - 3b cannot be combined. However, you can multiply and divide monomials with unlike terms. For example, 2a x 6b = 12ab.
If angle a = 54° and angle b = 20° what is the length of angle c?
| 63° | |
| 86° | |
| 76° | |
| 106° |
The sum of the interior angles of a triangle is 180°:
180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 54° - 20° = 106°
What is 6a9 - 2a9?
| a918 | |
| 4a9 | |
| 4 | |
| 12a9 |
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.
6a9 - 2a9 = 4a9
Find the value of a:
2a + z = -2
6a - 3z = 4
| 3\(\frac{9}{13}\) | |
| 2\(\frac{1}{8}\) | |
| \(\frac{46}{51}\) | |
| -\(\frac{1}{6}\) |
You need to find the value of a so solve the first equation in terms of z:
2a + z = -2
z = -2 - 2a
then substitute the result (-2 - 2a) into the second equation:
6a - 3(-2 - 2a) = 4
6a + (-3 x -2) + (-3 x -2a) = 4
6a + 6 + 6a = 4
6a + 6a = 4 - 6
12a = -2
a = \( \frac{-2}{12} \)
a = -\(\frac{1}{6}\)
The endpoints of this line segment are at (-2, 3) and (2, -3). What is the slope-intercept equation for this line?
| y = 2\(\frac{1}{2}\)x + 4 | |
| y = 3x + 1 | |
| y = -1\(\frac{1}{2}\)x + 0 | |
| y = -\(\frac{1}{2}\)x + 0 |
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, 3) and (2, -3) so the slope becomes:
m = \( \frac{\Delta y}{\Delta x} \) = \( \frac{(-3.0) - (3.0)}{(2) - (-2)} \) = \( \frac{-6}{4} \)Plugging these values into the slope-intercept equation:
y = -1\(\frac{1}{2}\)x + 0