i think the answer is 87.82
You make points with the x and y values after you solve the equation, ussually you will have to pick x values to plug into your equation. After that you use your x and y cordinants to graph points on a graph.
That is what I got ¡my teacher showed me that method in school .
X=60 Because 10+90 is 100 and 160-100 is 60, which is the number of players who play tennis and cricket.