To answer your questions based on the input-output table provided, we need to analyze the relationship between the input variable \( x \) and the output variable \( y \):
\[ \begin{array}{|c|c|} \hline x & y \ \hline -4 & 10 \ -1 & 5 \ 2 & -20 \ 5 & -35 \ \hline \end{array} \]
A. Write the linear equation that represents the input-output pairs in the table.
First, we can determine the slope \( m \) using two points from the table. Let's take \( (-1, 5) \) and \( (2, -20) \):
\[ m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{-20 - 5}{2 - (-1)} = \frac{-25}{3} = -\frac{25}{3} \]
Now let's find the y-intercept \( b \) using one of the points. Using \( (x, y) = (-1, 5) \):
\[ y = mx + b \ 5 = -\frac{25}{3}(-1) + b \ 5 = \frac{25}{3} + b \ b = 5 - \frac{25}{3} \ b = \frac{15}{3} - \frac{25}{3} = -\frac{10}{3} \]
Thus, the linear equation is:
\[ y = -\frac{25}{3}x - \frac{10}{3} \]
B. Create a real-world situation that could be modeled by the input-output pairs in the table.
Let's consider a situation involving the cost of producing a certain item where \( x \) is the number of items produced (or hours worked) and \( y \) is the amount of profit (or loss). For instance, if a factory incurs a loss when producing certain items, the table could represent the financial outcome in terms of profit/loss at different production levels.
C. Explain the meaning of the slope and y-intercept in the context of the situation described.
-
Slope: The slope of \( -\frac{25}{3} \) indicates that for every additional unit produced (or hour worked), the factory will lose approximately $8.33. This suggests that as production increases, the losses grow at a proportional rate.
-
Y-intercept: The y-intercept of \( -\frac{10}{3} \) (approximately -3.33) implies that if no items are produced (or no hours are worked), the factory still incurs a fixed cost of around $3.33 (for example, overhead costs), which results in a loss even without production.
D. Create a graph for the table.
To graph the equation \( y = -\frac{25}{3}x - \frac{10}{3} \) based on the points:
- Plot the points from the table: \((-4, 10)\), \((-1, 5)\), \( (2, -20)\), and \( (5, -35)\).
- Draw a straight line through these points to represent the linear equation.
E. Use the linear equation and graph to answer the following:
-
What is the change in the output value per unit change in the input value? The change in output value per unit change in input, represented by the slope, is approximately $-8.33 per additional item produced (i.e., \( -\frac{25}{3} \)).
-
What is the output value when the input value is 0? Substitute \( x = 0 \) into the linear equation:
\[ y = -\frac{25}{3}(0) - \frac{10}{3} = -\frac{10}{3} \approx -3.33 \]
So when no items are produced, the output value (loss) will be about -3.33.
-
What is the output value when the input value is 10? Substitute \( x = 10 \) into the linear equation:
\[ y = -\frac{25}{3}(10) - \frac{10}{3} = -\frac{250}{3} - \frac{10}{3} = -\frac{260}{3} \approx -86.67 \]
The output value (loss) when 10 items are produced will be approximately -86.67.
-
Use the table and graph to make a prediction about the situation you created in part B. Based on the trend shown in the table and the graph, as production increases, the losses will continue to grow. If the factory maintains or increases production without addressing the cost, it can expect to incur even larger financial losses. This indicates a need for revising production strategies or reducing costs to improve profitability.