Let's answer each question one by one:
3. Dr. Ellison says that the equation y = -3x + 7 has a solution of (2, 13). Is Dr. Ellison right or wrong? To check if (2, 13) is a solution, we substitute x = 2 into the equation: y = -3(2) + 7 y = -6 + 7 y = 1
Since the output is 1 (not 13), Dr. Ellison is wrong. Answer: B) Dr. Ellison is wrong.
4. A satellite TV company charges a one-time installation fee and a monthly service charge. The total cost is modeled by the function y = 99x + 15. Which statement represents the meaning of each part of the function? In the equation, y represents total cost, x represents the number of months of service, $99 is the installation fee, and $15 is the monthly service charge. Answer: A) y is the total cost, x is the number of months of service, $99 is the installation fee, and $15 is the service charge per month.
5. What is the rate of change of the table below? To find the rate of change, we look at the change in y over the change in x. The change in Y from 12 to 19 (increase of 7) occurs as x increases from 1 to 2 (increase of 1).
Rate of change = (change in Y) / (change in X) = (19 - 12) / (2 - 1) = 7 / 1 = 7. Answer: D) 7
7. What is the correct setup to finding the slope of a line that passes through the points (6, −3) and (−2, 7)? The formula for the slope \( m \) between two points (x1, y1) and (x2, y2) is: \[ m = \frac{y2 - y1}{x2 - x1} \] Let (x1, y1) = (6, -3) and (x2, y2) = (-2, 7). So, \[ m = \frac{7 - (-3)}{-2 - 6} = \frac{7 + 3}{-2 - 6} = \frac{10}{-8} = -\frac{5}{4} \]
To match the choices provided: Using the formula setup: \[ y2 - y1 = 7 - (-3) \] and \[ x2 - x1 = -2 - 6 \]
Thus, the correct expression for the slope setup is: Answer: C) 7 - (-3) / -2 - 6
8. Which equation of a line is parallel to the equation -4x + 3y = 12? To find a parallel line, we need to determine the slope of the given line. First, we rewrite the equation in slope-intercept form (y = mx + b): 3y = 4x + 12 y = (4/3)x + 4
The slope of this line is 4/3. Lines that are parallel have the same slope. We then look for a line with a slope of 4/3 from the choices given:
- A) y = 3x + 12 (slope = 3)
- B) y = −4/3x + 4 (slope = -4/3)
- C) y = 4/3x + 6 (slope = 4/3)
- D) y = 4x + 8 (slope = 4)
The only one with a slope of 4/3 is: Answer: C) y = 4/3x + 6