Question 768729
One way to do this is make a system of equations.  Use a form, mp+b=A.

Two equations from your data pairs are:
{{{m*11+b=1950}}} and {{{m*(11-7)+b=2250}}}, which is the system:
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{{{highlight(11m+b=1950)}}}
{{{highlight(4m+b=2250)}}}
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Solve the equations for m and b any way you want; substitution, elimination, graphing.