Linear Function:
All the graphs are straight lines and these relations are called linear
functions. All these relations are generally written in the form of y = mx
or y = mx + c.
Slopeintercept form of a linear equation:
The straight lines in the form of y = mx + c are know as slope intercept form
where m is the slope and c is the yintercept.
Draw the following graphs:
y = x + 3 and y = x  2.
Ordered pairs for the graph y = x + 3
x  3  2  1  0  1  2  3 
y = x + 3  0  1  2  3  4  5 
6 
Ordered pairs  (3,0)  (2,1)  (1,2)  (0,3)  (1,4)  (2,5)  (3,6) 
Ordered pairs for the graph y = x  2
x  3  2  1  0  1  2  3 
4 
y = x  2  5  4  3  2  1  0 
1  2 
Ordered pairs  (3,5)  (2,4)  (1,3)  (0,2)  (1,1)  (2,0)  (3,1) 
(4,2) 
Observing above graphs:
1. y = x + 3 and y = x  2 are straight lines.
2. y = x + 3 intersect the Y  axis at (0,3), the distance between the origin and the point of intersecting of the straight line with Y  axis is known as yintercept and it is equal to
the ycoordinate of the point. yintercept for this straight line is 3.
3. y = x  2 intersect the Yaxis at (0,2). The distance between the origin and the point of intersection of the straight line with Yaxis is known as yintercept and it is equal to the ycoordinate of that point. yintercept for this
straight line is 2.
Directions: Draw the following graphs:
y = x+1
y = x+2
y = x+4
y = x+5
y = x1
y = x3
y = x4
y = x5
y = x6
