Which points satisfy the following system of linear inequalities? show all your work. -5y+4x< 18 -15y-9x> 117

The lines intersect on the graph at (-3, -6).  The solution set falls within the domain of negative infinity to positive infinity and a range of y is greater than or equal to -6.  Without having the capabilities of graphing it to show you, that's the best I can do. Graph the lines (dotted, I presume) and see if you can follow those guidelines for the solution set.