Question

The graph below is represented by which system of inequalities?

-x + 3y < 9
y > -2x + 1

-x + 3y less than or equal to 9
y > -2x + 1

-x + 3y < 9
y greater than or equal to -2x + 1

None of these systems represent the graph shown.

Answer 1

@mathmale

Answer 2

Hello. The approach I'd favor would be to re-write the 2 given inequalties so that they appear to have been solved for y:

-x + 3y < 9 => 3y < 9 + x => y < 3 + x/3
y > -2x + 1 => y + 2x > 1 => y > -2x + 1

Then I'd compare these results with the 3 answer choices given. Any match? If so, then you'll have the correct answer. Similar info could be obtained from the graph, but I think this analytic approach is faster.

Answer 3

So, y is greater than or equal to 4 + -2x/3?

Answer 4

Oh, wait. I see.

Answer 5

Thanks xD