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During one month, a homeowner used 200 units of electricity and 110 units of gas for a total cost of $87.80.
The next month, 240 units of electricity and 200 units of gas were used for a total cost of $117.60.
Find the cost per unit of gas.
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Write the system of two equations
200e + 110g = 87.80
240e + 200g = 117.60
where "e" is the price for the unit of electricity and "g" is the price for the unit of gas.
Solve using determinants
g = = 0.18.
ANSWER. The cost per unit of gas is 0.18.
Solved.
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On the Determinants' method for solving systems of two linear equations in two unknowns see the lesson
- Solution of the linear system of two equations in two unknowns using determinant
in this site.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lesson is the part of this online textbook under the topic "Systems of two linear equations in two unknowns".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.