For finding the system of equations you can use one of two methods. There's the elimination method and also the substitution method. For this I think the best way we could go at solving this is by using the elimination method. Since we can eliminate the 2y. We can then solve for x and then we'll go from there.
Now that we know what x is we can substitute it for one of the equations and then we will be able to solve for y.
So now we have the x and the y and once we place them together we can get the solution of those two equations, and the solution is .
The inequality for this problem would be 3.25x > 210 with x representing the number of tacos sold per day. The answer to this inequality would be x = 65 (actually 64.61 but you can't sell half a taco). The taco stand needs to sell at least 65 tacos a day to make a profit.