Solution
a)
The cost C is the dependent variable because the cost depends on the time t.
Cost 'c' = dependent variable
Time 't' = Independent variable
b)
By substituting t = 5 in the equation c = 2.5t + 6
Time, t 2.5t + 6 Total cost (c)
5 2.5(5) + 6 18.5
c)
First, by substituting t = 1/2 in the total cost equation.
[tex]\begin{gathered} \text{Total cost c = 2.5t + 6} \\ c\text{ = 2.5 }\times\frac{1}{2}\text{ + 6} \\ \text{c = 1.25 + 6 } \\ \text{c = \$7.25} \end{gathered}[/tex]
Second, by drawing a line from the x-axis at t = 1/2 to intersect the graph and then trace the point to the y-axis.
d)
The equation is y = 3x + 5, where y and x are two variables.
To plot a table, choose a range of values of variable x and find the corresponding value of y.
Plot the graph using x as the horizontal axis and y as the vertical axis.
