Answer:
1a) 75 degrees
1b) 105 degrees
1c) 75 degrees
1d) 105 degrees
Slope of AC: -1.5x
Slope of XY: -2/3x
Neither: Why? The slope of AC and XY are not the same, so they are not parallel. They are not perpendicular either because being perpendicular means that the slopes must be the negative reciprocal, which it is not.
Explanation: