The cost of custom-made cookies at a bakery is shown on the graph below, where x represents the number of cookies and y represents the total cost.
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The equation of a line is given by:
[tex]y=mx+b[/tex]where m is the slope and b is the y intercept. From the graph we notice that b=1. To find the slope we need to use the formula:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]Using the first two points on the graph (0,1) and (1,3) we have that the slope is:
[tex]m=\frac{3-1}{1-0}=\frac{2}{1}=2[/tex]Plugging the values in the first equation we have that the equationwe are looking for is:
[tex]y=2x+1[/tex]