Answer:
4/3
Step-by-step explanation:
Assuming your line is intended to be ...
y = -3/4x +6
The slope is the coefficient of x: -3/4.
The slope of a line perpendicular to it is the opposite of the reciprocal of this, so is ...
-1/(-3/4) = 4/3
The gradient of the perpendicular line is 4/3.
