SolvingSystems.Substitution

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** The Substitution Method **. This is another method to solving linear equations. It involves plugging in the value of a number into another equation. Basically, if we have y=3x and 2y+2x-5=15, you plug in 3x for y, so it would be 2(3x)+2x-5=15. It's really a lot easier than it sounds. I only use it if one is in slope intercept form and the other is in standard form. **It works best if one variable is by itself (alone on one side of the equation).** y=3x+1 5x+2y=13 You plug in what y is equal to from the first equation into the second one. 5x+2(3x+1)=13 11x+2=13 11x=11 x=1 Then you plug the x value you just found into the first equation. y=3(1)+1 y=4 **After this, you may want to plug in the numbers into the original equations to check and make sure you are correct.** 4=3(1)+1 5(1)+2(4)=13  Both of these are correct, therefore x=1 and y=4, and your answer is (1,4).

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