Answer:
- 2
Step-by-step explanation:
1) Write the equation in slope-intercept form.
4x - 8y = 64
-8y = -4x +64
y = 1/2 x - 8
slope of this line = 1/2
2) For perpendicular line the slope is negative reciprocal.
So, slope for perpendicular line is equal -2.
