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How to I solve this linear system using method of substitution?

1/4x + 1/2y = -5/12
2x - y = -4/3

2 answers

To do substitution, choose one of the equations. Then choose a variable in that equation, and express it in terms of the other variable. Finally, substitute it to the other equation.

Here, let's choose the 2nd equation.
2x - y = -4/3

Then let's choose the variable y. Express it in terms of the other:
2x - y = -4/3
-y = -4/3 - 2x
y = 2x + 4/3

Now, substitute this to the 1st equation:
1/4x + 1/2y = -5/12
1/4x + 1/2(2x + 4/3) = -5/12
1/4x + x + 2/3 = -5/12
5/4x = -5/12 - 2/3
5/4x = -5/12 - 8/12
5/4x = -13/12
x = -13/12 * 4/5
x = -13/15

Now that you have a value for x, substitute this to either equation to get the value of y.
Hope this helps~ `u`
THANK YOUUUU =)