Solve the following pair of equations by substitution method:
$7x - 15y = 2$ $...(1)$
$x + 2y = 3$ $...(2)$

(N/A) Step $1:$ We pick either of the equations and write one variable in terms of the other. Let us consider Equation $(2)$.
$x + 2y = 3$
We can write it as $x = 3 - 2y$ $...(3)$
Step $2:$ Substitute the value of $x$ from Equation $(3)$ into Equation $(1)$. We get:
$7(3 - 2y) - 15y = 2$
$21 - 14y - 15y = 2$
$-29y = 2 - 21$
$-29y = -19$
Therefore,$y = \frac{19}{29}$
Step $3:$ Substituting this value of $y$ in Equation $(3)$,we get:
$x = 3 - 2\left(\frac{19}{29}\right)$
$x = 3 - \frac{38}{29}$
$x = \frac{87 - 38}{29} = \frac{49}{29}$
Therefore,the solution is $x = \frac{49}{29}, y = \frac{19}{29}$.