Solve for x, y
x=\frac{8\left(X-150\right)}{5}
y=500-X
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y+X=500,80y+50x=28000
To solve a pair of equations using substitution, first solve one of the equations for one of the variables. Then substitute the result for that variable in the other equation.
y+X=500
Pick one of the two equations which is more simple to solve for y by isolating y on the left hand side of the equal sign.
y=500-X
Subtract X from both sides of the equation.
80\left(500-X\right)+50x=28000
Substitute 500-X for y in the other equation, 80y+50x=28000.
40000-80X+50x=28000
Multiply 80 times 500-X.
50x=80X-12000
Subtract 40000-80X from both sides of the equation.
x=\frac{8X}{5}-240
Divide both sides by 50.
y=500-X,x=\frac{8X}{5}-240
The system is now solved.
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