Solve for x, y
x=250-3v
y=3\left(v-50\right)
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Algebra
\left. \begin{array} { l } { x + y = 100 } \\ { 0.2 x + 0.6 v = 50 } \end{array} \right.
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0.2x+\frac{3v}{5}=50,x+y=100
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.
0.2x+\frac{3v}{5}=50
Pick one of the two equations which is more simple to solve for x by isolating x on the left hand side of the equal sign.
0.2x=-\frac{3v}{5}+50
Subtract \frac{3v}{5} from both sides of the equation.
x=250-3v
Multiply both sides by 5.
250-3v+y=100
Substitute 250-3v for x in the other equation, x+y=100.
y=3v-150
Subtract 250-3v from both sides of the equation.
x=250-3v,y=3v-150
The system is now solved.
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