Question 180188
<font face="Times New Roman" size="+2">


Here you have a situation where the value 3 maps to the value 30 and the value 4 maps to the value 25.  This is exactly the same as saying that you have two ordered pairs defining a straight line and the two ordered pairs are (3, 30) and (4, 25).


Notice that when the <i>x</i> value increases by 1, the <i>y</i> value decreases by 5.  That means that the slope of our line is -5.  Also notice, using this slope number, that 2 would map to 35, 1 would map to 40, and 0 would map to 45.  That tells us that the <i>y</i>-intercept of the line is 45.


Now we can write the equation in slope intercept form directly:


*[tex \Large y = -5x + 45]


To calculate the sales at a $5 price point, substitute 5 for <i>x</i> and do the arithmetic.



John
*[tex \LARGE e^{i\pi} + 1 = 0]
</font>