Solve the following pair of linear equations using a graph: $3x + 6y = 3900, x + 3y = 1300$

(N/A) For the equation $3x + 6y = 3900$:
Dividing by $3$,we get $x + 2y = 1300$,which implies $y = \frac{1300 - x}{2}$.
If $x = 0$,$y = 650$. If $x = 1300$,$y = 0$.

$x$	$0$	$1300$
$y$	$650$	$0$

Plot the points $(0, 650)$ and $(1300, 0)$ and join them to draw the line.
For the equation $x + 3y = 1300$:
This implies $y = \frac{1300 - x}{3}$.
If $x = 1300$,$y = 0$. If $x = 100$,$y = 400$.

$x$	$1300$	$100$
$y$	$0$	$400$

Plot the points $(1300, 0)$ and $(100, 400)$ and join them to draw the line.
The intersection point of these two lines is $(1300, 0)$,which satisfies both equations.
Thus,the solution is $x = 1300, y = 0$.