CORE Coordinate Geometry and Transformations - New Indian ...

We can always write a linear equation in two variables in the form
y = mx + c
For example, the equation 2x + 3y = 6, can be written as
y = x +
If is of the form
y = mx + c, where m = and c = 2.
Similarly,
x – y = -5 can be written as
If is of the form
and so on.
y = x + 5
y = mx + c, where m = 1 and c = 5
The graph of y = mx + c is a straight line (as it is a linear equation in two variables).
m is called the gradient which refers to “steepness” or slope of the line and c is called
the y-intercept of the line.
As you can see from the above examples, the gradient of a straight line representing
2x + 3y = 6, i.e. y = x + 2
is given by m = and c = y – intercept = 2 (See Fig 9)
Similarly, the gradient of the straight line representing
x – y = -5, i.e. y = x + 5 is 1 and c = 5 (See Fig 10)
21