Question 776305
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No, you don't need to take the "12 months per year" into account.  You have two data points: (4, 4500) and (10, 5400).  Since the problem implies a fixed annual increase, the function must be linear.


Use the two-point form of an equation of a line:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y\ -\ y_1\ =\ \left(\frac{y_1\ -\ y_2}{x_1\ -\ x_2}\right)(x\ -\ x_1) ]


where *[tex \Large \left(x_1,y_1\right)] and *[tex \Large \left(x_2,y_2\right)] are the coordinates of the given points.


Simplify and put the equation into slope-intercept form, *[tex \LARGE y\ =\ mx\ +\ b]


Then *[tex \LARGE b] will be the initial monthly salary and *[tex \LARGE m] will be the annual increment.


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
<font face="Math1" size="+2">Egw to Beta kai to Sigma</font>
My calculator said it, I believe it, that settles it
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