Show graphically that each one of the following systems of equations has infinitely many solutions:
$x-2 y=5$
$3 x-6 y=15$
The given equations are
$x-2 y=5$ ...(i)
$3 x-6 y=15$...(ii)
Putting $x=0$ in equation $(i)$, we get:
$\Rightarrow 0-2 y=5$
$\Rightarrow y=-5 / 2$
$x=0, \quad y=-5 / 2$
Putting $y=0$ in equations $(i)$ we get:
$\Rightarrow x-2 \times 0=5$
$\Rightarrow x=5$
$x=5, \quad y=0$
Use the following table to draw the graph.
Draw the graph by plotting the two points $A(0,-5 / 2)$ and $B(5,0)$ from table
Graph of the equation….
$3 x-6 y=15$..(ii)
Putting $x=0$ in equations $(i i)$ we get:
$\Rightarrow 3 x-6 \times 0=15$
$\Rightarrow x=5$
$x=5, \quad y=0$
Use the following table to draw the graph.
Draw the graph by plotting the two points $C(0,-5 / 2)$ and $D(5,0)$ from table.
Thus the graph of the two equations coincide
Consequently, every solution of one equation is a solution of the other.
Hence the equations have infinitely many solutions.