y = -1/2x - 3....slope here is -1/2. A perpendicular line will have a negative reciprocal slope. All that means is " flip " the slope and change the sign. So we need a slope of 2 for our perpendicular line.
y = mx + b
slope(m) = 2
(6,-4)...x = 6 and y = -4
now we sub and find b
-4 = 2(6) + b
-4 = 12 + b
-4 - 12 = b
-16 = b
so ur perpendicular equation is : y = 2x - 16