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What is the solution of x + y = 18 and x -y =2

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needyourhelp | Student, Kindergarten | eNoter

Posted September 17, 2013 at 4:54 AM via web

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What is the solution of x + y = 18 and x -y =2

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justaguide | College Teacher | (Level 2) Distinguished Educator

Posted September 17, 2013 at 4:56 AM (Answer #1)

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The set of equations x + y = 18 and x - y = 2 has to be solved.

Add the two equations: 2x = 20 => x = 10

y = 18 - 10 = 8

The solution of the set of equations is (10, 8)

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baxthum8 | High School Teacher | (Level 3) Associate Educator

Posted September 17, 2013 at 8:57 PM (Answer #2)

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Solve:  x + y = 18

           x - y = -2

If we add the 2 equations together we'd have;

2x + 0y = 16, therefore `2x = 16.`

If 2x = 16, divide both sides by 2 and `x = 8.`

By substituting, x = 8, into either of the equations we can solve for y.

`8 + y = 18`

` `Subtract 8 from both sides:  `y = 10`

This gives us the solution:  x = 8 and y = 10

or (8, 10)

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