Question

Maria graphed the inequality y < -x + 1 as shown in the image.

What mistake did Maria make when graphing the inequality?

1. Maria graphed the slope of the line incorrectly. The slope should be m = 1, but Maria graphed a line with slope m = -1.

2. Maria graphed the incorrect y-intercept. The y-intercept should be (0, -1).

3. Maria used a solid line for her graph, when she should have used a dashed/dotted line.

4. Maria shaded the incorrect half of the graph. The graph should be shaded ABOVE the line instead.

Answer 1

3. Maria used a solid line for her graph, when she should have used a dashed/dotted line.

How to represent inequality on a graph.

Maria's inequality, y < -x + 1 represents a dashed line (not including points on the line) with a slope of -1 and a y-intercept at 1. Shade below the line indicates solutions satisfying y < -x + 1. The dashed line signifies the exclusion of points directly on the line from the solution set.

But, Maria used a solid line for her graph, when she should have used a dashed/dotted line.