Question 631365
Define the following variables:
Total Cost T=5120
Total Installation Cost = I
Materials Cost M=2840
Area of Living Room = A
Installation Cost/ft^2 C=1.9

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The total cost for the job (T) can be expressed by the following equation:
{{{T=I+M}}}
{{{5120=I+2840}}}
{{{I=2280}}}

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Now that you know the total installation cost, you can apply the following formula to determine the area of the living room (A).

{{{I=CA}}}


Substitute previous found value for I:
{{{2280=1.9A}}}
{{{A=2280/1.9}}}
{{{highlight(A=1200 ft^2)}}}

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Good Luck,
tutor_paul@yahoo.com