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When using the substitution method what is the system of equations
x+y=5
6x+3y=27

User Havakok
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1 Answer

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Answer:

y = 5 -x

6x +3(5 -x) = 27

Explanation:

The first equation is conveniently solved for either x or y. If we solve it for y, we get ...

y = 5 - x . . . . . . subtract x from both sides

This expression for y can be substituted into the second equation to give ...

6x +3(5 -x) = 27

These are your new system of equations.

Simplified, they are ...

  • y = 5 -x
  • 3x +15 = 27

_____

The second is a 2-step equation that gives the value of x, which can then be used in the first equation to find y.

3x = 12 . . . . subtract 15

x = 4 . . . . . . divide by 3

y = 5 -4 = 1 . . . . substitute into the first equation

The solution is (x, y) = (4, 1).

User Littles
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