If $y = \frac{1}{2} x$ and $x + 2y = 8$,then $x = \dots$

Solve the following pair of linear equations by the method of substitution: $8x - 3y = 1$ and $34x - 3y = 14$.

Solve the following pair of linear equations by the method of substitution: $x + 11y = 1$ and $8x + 13y = 2$.

If $2x + y = 35$ and $3x + 4y = 65$,then find $\frac{x}{y}$.

The sum of the present age of a father and twice the present age of a son is $70$ years. Also,the sum of twice the present age of father and the present age of son is $95$ years. Find their present ages.

If $x = -2$ and $\frac{4}{x} + \frac{3}{y} = 1$,then $y = \dots$