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Re: If x – y = 4 and 2x + y = 5, what is the value of x?
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16 Jul 2018, 07:01
Explanation
Notice that the first equation has the term –y while the second equation has the term +y.
While it is possible to use the substitution method, summing the equations together will make –y and y cancel, so this is the easiest way to solve for x.
x – y = 4
2x + y = 5
Adding the equations above
3x = 9
x = 3