McGraw Hill Glencoe Algebra 1, 2012
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McGraw Hill Glencoe Algebra 1, 2012 View details
2. Writing Equations in Slope-Intercept Form
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Exercise 45 Page 231

a We are asked to determine the processing fee and write a linear equation to represent the total cost for tickets. Each ticket costs Also, we know that Jackson ordered tickets and the cost was Let's start by determining the processing fee and linear equation that represents the total cost We can model it with a linear equation.
In this form the cost increases with the number of tickets bought. In this case, the intercept is represented by the processing fee, which is fixed. We do not know this fee yet, but we do know that each extra ticket costs So far, we can substitute into our equation.
We also know that tickets cost By substituting into the equation and solving for we can determine the processing fee.
Solve for
Now we can write the final equation.
b Let's make a table of values for and
c To graph the equation, we plot the three points found in Part B and connect them with a straight line. Note that we neither have a negative number of tickets bought nor a negative cost, so our graph cannot take negative values.

To predict the cost of tickets, we start at on the horizontal axis and go up until we hit the graph. After having hit the graph, we can determine the corresponding cost on the vertical axis.

It looks like the cost is around and In other words, about The equation we get in Part A can help us to find a more exact value.
From the equation, we can see that the slope is A slope of means that for every horizontal step in the positive direction, we take 52 vertical steps in the positive direction. We know that the line passes through By adding to we can predict the value of tickets.
Therefore, the value of tickets would be