SOLUTION: Please help I am getting confused...I need to solve each system by the substitution method.
{{{x+3y=2}}} first
{{{-x+y=1}}} second
thanks so much
Question 124955: Please help I am getting confused...I need to solve each system by the substitution method.
first second
thanks so much Found 2 solutions by iluvbuilding429, jim_thompson5910:Answer by iluvbuilding429(41) (Show Source): You can put this solution on YOUR website! Please help I am getting confused...I need to solve each system by the substitution method.
first second
thanks so much
Solve: We'll use substitution. After moving 3*y to the right, we get: , or . Substitute that
into another equation: and simplify: So, we know that y=0.75. Since , x=-0.25.
Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for y.
So let's isolate y in the first equation
Start with the first equation
Subtract from both sides
Rearrange the equation
Divide both sides by
Break up the fraction
Reduce
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Since , we can now replace each in the second equation with to solve for
Plug in into the first equation. In other words, replace each with . Notice we've eliminated the variables. So we now have a simple equation with one unknown.
Multiply both sides by the LCM of 3. This will eliminate the fractions (note: if you need help with finding the LCM, check out this solver)