Explanation for Question 4 From the Math (No Calc) Section on the 2018 April Sat
Question four asks in the X, 2 Y plane point a is contained in the graph of the solution set of 3 the system of inequalities above which of the following could be the coordinates of 4 point a. So I'm just going to start by rewriting these two inequalities 5 as one inequality. 6 And to do that, I'm just going to write it like this. 7 I give two X plus 11 with Y in the middle. 8 Now I'm going to go through our answer choices and I'm going to plug 9 them in and see if they are correct. So three times 10 two minus nine, that's just six minus. 11 Mine are negative. Three is less than Y, 12 which is one which is greater than or equal to negative two 13 times X, which is negative two times two plus 14 11, negative two times two is negative four plus 11 is positive 15 seven. So that is incorrect. 16 And we can eliminate answer choice. Next we can, 17 uh, input answer choice B. So three times four 18 minus nine is less than one, 19 which is greater than or equal to negative. 20 Two times four plus 11, 21 three times four is 12 minus nine is three, 22 which is not less than one. So we already know answer. 23 Choice B is wrong. I'm just going to raise this to make a little 24 more room to test, answer choice C. 25 So now let's plug in four or five. 26 So three times four minus nine is less than five, 27 which is greater than or equal to negative two times four plus 11, 28 three times four is 12 minus minus three, 29 which is less than five and negative. 30 Two times four is negative eight plus 11 is three and 31 five is greater than or equal to three. 32 So we know that answer choice C is correct.