The instructor at a stretching class noticed that in a group of 20, 10 people wore only socks, 3 people wore only shoes, and a total of 9 people wore socks or shoes (some people wore both). Determine how many people wore socks and shoes.

7 people have socks and shoes

Step-by-step explanation:

20-10= 10, eliminated because they have socks

10 - 3 = 7 , eliminated because they have shoes

When they ask for X, you are generally supposed to look at all the points in which the line intercepts the X axis. So that would be -2, 1, and 3.

PS. even if it asked for Y, instead of X, you would do the same thing.