\left\{ \begin{array} { l } { y = \frac { \sqrt { 15 } } { 14 } } \\ { \sqrt { 15 } x + y - 4 \sqrt { 15 } = 1 } \end{array} \right.
Solve for y, x
x=\frac{\sqrt{15}}{15}+\frac{55}{14}\approx 4.186770318
y=\frac{\sqrt{15}}{14}\approx 0.276641668
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y=\frac{\sqrt{15}}{14},y+\sqrt{15}x-4\sqrt{15}=1
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=\frac{\sqrt{15}}{14}
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.
\frac{\sqrt{15}}{14}+\sqrt{15}x-4\sqrt{15}=1
Substitute \frac{\sqrt{15}}{14} for y in the other equation, y+\sqrt{15}x-4\sqrt{15}=1.
\sqrt{15}x-\frac{55\sqrt{15}}{14}=1
Add \frac{\sqrt{15}}{14} to -4\sqrt{15}.
\sqrt{15}x=\frac{55\sqrt{15}}{14}+1
Add \frac{55\sqrt{15}}{14} to both sides of the equation.
x=\frac{\sqrt{15}}{15}+\frac{55}{14}
Divide both sides by \sqrt{15}.
y=\frac{\sqrt{15}}{14},x=\frac{\sqrt{15}}{15}+\frac{55}{14}
The system is now solved.
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