Question

The following inequalities form a system.

y ≥ 3x + 1

x < −3


Which graph represents the system?


A) The graph shows a solid line, which passes through a point 0 comma 1 and a point 1 comma 4, with shading above the line. There is also a dashed line, which passes through a point 0 comma negative 3 and a point 1 comma negative 3, with shading below the line.

B) The graph shows a solid line, which passes through a point 0 comma 1 and a point 1 comma 4, with shading below the line. There is also a dashed line, which passes through a point 0 comma negative 3 and a point 1 comma negative 3, with shading below the line.

C) The graph shows a solid line, which passes through a point 0 comma 1 and a point 1 comma 4, with shading above the line. There is also a dashed line, which passes through a point negative 3 comma 0 and a point negative 3 comma 1, with shading to the right of the line.

D) The graph shows a solid line, which passes through a point 0 comma 1 and a point 1 comma 4, with shading above the line. There is also a dashed line, which passes through a point negative 3 comma 0 and a point negative 3 comma 1, with shading to the left of the line.

Answer 1

The graph that represents the system is option D.

The first inequality y ≥ 3x + 1 represents a line with a slope of 3 and a y-intercept of 1, and it is shaded above the line. This line is a solid line.

The second inequality x < -3 represents a vertical line with an x-intercept of -3, and it is shaded to the left of the line. This line is a dashed line.

The solution of the system is the intersection of the two regions, which is the area on the coordinate plane that is shaded above the solid line and to the left of the dashed line.

So the graph that represents the system is the one that shows a solid line with a slope of 3 and a y-intercept of 1, with shading above the line, and a dashed line with an x-intercept of -3, with shading to the left of the line. This is option D.