Explanation for Question 9 From the Math (No Calc) Section on the 2017 October Sat
Question nine says a system of three equations is graft in the X, 2 Y plane above. How many solutions does the system have? 3 So for a system of equations to have a solution, 4 that means that the system must intersect. 5 And since there are three different lines in the system of equations or three 6 different equations for there to be a solution, 7 all three of the lines have to intersect, 8 which means that like an intersection like this one over here, 9 doesn't count as a solution because only two of the lines intersect. 10 There's only one point on this graph where all three lines intersect. 11 And that's this 0.1 right here, 12 negative one three, which means that there's only one solution 13 to this system of equations.