Answer:
y = -2x - 9
Explanation:
The equation given, y = 1/2x -3, is a linear equation. Lines that are perpendicular to linear equations have slopes that are the reciprocal opposite of the given line. Since the slope of the given line is 1/2, the reciprocal opposite is: -2. Now that you have the slope and a point, you can use slope-intercept formula to solve for 'b':
y = mx + b
-5 = -2(-2) + b
-5 = 4 + b
-9 = b
-2 = m
y = -2m - 9