Final answer:
Lines a) and b) are perpendicular to y = -1/2x + 4.
Step-by-step explanation:
To determine which of the given lines are perpendicular to the line y = -1/2x + 4, we need to find the negative reciprocal of the slope of the given line. The slope of y = -1/2x + 4 is -1/2. The negative reciprocal of -1/2 is 2.
Now, let's check the slopes of the given lines:
a) 2x - y = 1: The slope is 2, which is the negative reciprocal of -1/2.
b) y = 2x: The slope is 2, which is the negative reciprocal of -1/2.
c) 2x + y = 1: The slope is -2, which is not the negative reciprocal of -1/2.
d) 1/2x - y = 3: The slope is 1/2, which is not the negative reciprocal of -1/2.
e) 2x - y = 3: The slope is 2, which is the negative reciprocal of -1/2.
Therefore, the lines a) and b) are perpendicular to y = -1/2x + 4.