What is the equation of the line perpendicular to the line y = 4/9 x _ 2 that passes through the point (4,3)?

If the line is perpendicular to the line: y = 4/9 x - 2,
then : m = ( - 1 ) : ( 4/9 ) = - 9/4
y = m x + b
3 = - 9/4 * 4 + b
3 = - 9 + b
b = 3 + 9
b = 12

The equation is:
y = - 9/4 x + 12

It would be 18 cm