Draw the graph of each of the following linear equations in two variables:
(i) y = 3x
(ii) 3 = 2x + y
(i) y = 3x
To draw a graph of linear equations in two variables, let us find out the points to plot.
To find out the points, we have to find the values which x and y can have, satisfying the equation.
Here,
y = 3x
Substituting the values for x,
When x = 0,
y = 3x
y = 3 × 0
y = 0
When x = 1,
y = 3x
y = 3×1
y = 3
x → 0, 1
y → 0, 3
The points to be plotted are (0, 0) and (1, 3)
(ii) 3 = 2x + y
To draw a graph of linear equations in two variables, let us find out the points to plot.
To find out the points, we have to find the values which x and y can have, satisfying the equation.
Here,
3 = 2x+y
Substituting the values for x,
When x = 0,
3 = 2x+y
3 = 2×0+y
3 = 0+y
y = 3
When x = 1,
3= 2x+y
3 = 2×1+y
3 = 2+y
y = 3–2
y = 1
x → 0, 1
y → 3, 1
The points to be plotted are (0, 0) and (1, 3)