Use the method of elimination to find the solution of the following pair of linear equations: $0.4 x + 0.3 y = 1.7, 0.7 x - 0.2 y = 0.8$

If the following pair of equations is consistent (unique solution),then find the value of $k$:
$x - ky = 2$
$3x + 2y = -5$

The sum and difference of the reciprocals of the ages of a son and father are respectively $\frac{5}{40}$ and $\frac{3}{40}$. Represent this as a pair of linear equations in two variables,where $x$ is the age of the son and $y$ is the age of the father.

By the graphical method,find whether the following pair of equations are consistent or not. If consistent,solve them.
$3x + y + 4 = 0$
$6x - 2y + 4 = 0$

The solution set of the pair of equations $2x + 3y = 4$ and $6x + 9y = 17$ is ............

Solve the following pair of equations by the method of elimination:
$x + 2y = \frac{3}{2}$
$2x + y = \frac{3}{2}$