Question

Find the y-intercpt of the line passing through the pints (-1,3) and (4,6)

Answer 1

 The points are (-1, 3) and (4, 6)

The two points form of a line equation

y - y1  =  [(y2 - y1) / (x2 - x1)] X (x - x1) ------------> (1)

Substitute (x1, y1) = (-1, 3) and (x2, y2) = (4, 6) in Eq (1)

y - 3  =  [ (6 - 3) / (4 - (-1)) ] X [ x - (-1) ]

y - 3  =  [ 3 / (4 + 1) ] X ( x + 1)

y - 3  =   3 / 5 X ( x + 1)

5 (y - 3)  =   3 ( x + 1)

5 y - 15  =   3x + 3

5y  =  3x + 3 + 15

5y  =  3x + 18

To find out y - intercept Substitute x = 0 in above equation

5y  =  3(0) + 18

5y  =  18

y  =  18/5.

Answer :

y - intercept is  18/5.