Line equations

Question

A straight line, L, is perpendicular to the line with equation y=4x+3

L passes through the point (7,3)

Find equation for L

Answer 1

The slope of the given line is 4.

 

The PERPENDICULAR LINE has slope -1/4, the NEGATIVE RECIPROCAL 

 

intercept B = y - m x

 

                 = 3 - ( -1/4)(7)

 

                  = 3 + 7/4

 

                   = 12/4 + 7/4

 

                   = 19/4

 

The perpendicular line has equation y = (-1/4)X + 19/4