If the point $(3, 5)$ lies on the graph of the equation $ax + y = 20$,find the value of $a$.

Determine which of the given equations is represented by the graph shown in the figure below.

State whether the following statement is True or False and justify your answer:
Every point on the graph of a linear equation in two variables does not represent a solution of the linear equation.

If the graph of the equation $ax + 3y = 21$ passes through the point $(5, 2)$,then the value of $a = \ldots$

Write the linear equation such that each point on its graph has an ordinate $3$ times its abscissa.

For the equation $3x - 2y = 12$,express $y$ in terms of $x$.