Explanation for Question 12 From the Math (No Calc) Section on the 2019 March Sat
Question 12 asks, which of the following could be an equation for the graph 2 shown in the X, Y plane above. 3 So the find the answer to this question, we're going to need to find 4 two things, the slope of this line and the Y intercept. 5 And that's because once we have those two pieces of information, 6 we can create a line in the Y equals MX plus B form, 7 but I've written out over here. So let's start by finding the Y intercept. 8 All we have to do is go to the Y axis and see where 9 the line crosses. And that happens at 1, 2, 3, 4. 10 So we know that the Y intercept is four. 11 Therefore we can erase or cross out a N D. 12 So this is what we know the line is thus far. 13 Now, the next thing that we need to do is find the slope. 14 So I'm just going to pick this point here, and this point here, 15 and I'm going to use those points to figure out the rise of the 16 audience. Now you could plug this into a slope formula, 17 which I've written out over here, but I'm just going to count how many 18 units we go down and how many we go over. 19 So we're going down 1, 2, 3, 4 units. 20 So negative four is the rise. And the run is 2, 4, 6, 8, 10, 12. 21 So our slope is negative four over 12, 22 or simplified negative one over three. 23 And therefore the answer is C.