SOLUTION: How to solve:3x-y=23,x/3+y/4=4 using the method of elimination by equating coefficients.

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Question 1083497: How to solve:3x-y=23,x/3+y/4=4 using the method of elimination by equating coefficients.

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
3x - y = 23,   (1)
x%2F3+%2B+y%2F4 = 4.      (2)

Multiply equation (2) by 12 (both sides) to rid off the denominators.  You will get


3x -  y = 23,   (1')
4x + 3y = 48.   (2')

To eliminate "y", multiply the equation (1') by 3 (both sides). You will get

9x - 3y = 69,    (1'')
4x + 3y = 48.    (2'')

Now add equations (1'') and (2'')  (both sides).  You will get

9x + 4x = 117  ====>  13x = 117  ====>  x = 117%2F13 = 9.

Now y = 3x - 23 = 3*9 - 23 = 27 - 23 = 4.


Answer.  x = 9,  y = 4.

Solved.


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On solving systems of linear equations in two unknowns see the lessons
    - Solution of a linear system of two equations in two unknowns by the Substitution method
    - Solution of a linear system of two equations in two unknowns by the Elimination method
    - Solution of a linear system of two equations in two unknowns using determinant
    - Geometric interpretation of a linear system of two equations in two unknowns
    - Solving word problems using linear systems of two equations in two unknowns
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 lessons are the part of this online textbook under the topic "Systems of two linear equations in two unknowns".