Explanation for Question 8 From the Math (No Calc) Section on the 2019 October Sat
Now in question number eight were asked, which of the following is the graph 2 of this equation, right? And the equation that they give us is Y 3 minus five X is equal to negative six. 4 And so the real key to solving this question is realizing that 5 this, uh, form of the equation of a line is not a typical form 6 that we're used to. If you're ever trying to take an equation and turn 7 it into a graph you want to use Y intercept form, 8 which is Y equals MX plus B. 9 But in this case, our X is on the left side, 10 not on the right side of the equal sign. 11 So what we need to do is we need to take this X and 12 move it over to the right side of the equation. 13 That's why it's with the minus six. Now, 14 if I'm trying to take that minus five X and move it from left 15 to, right, that means I need to add five X to both sides, 16 because that will allow the Xs to cancel on my left, 17 leaving me with just Y and then I'll have a plus five X, 18 which I can just write, um, is five X minus six. 19 And now our equation is in a slope intercept form. 20 We can see that we have a slope of five. So our slope is 21 a positive number. It's a positive five. And our Y intercept is negative six. 22 If we look at the graph on a, we can see that the Y 23 intercept is correct. The Y intercept is at negative six, 24 but we have a negative slope, right? 25 Because the graph is going down like this, 26 and we don't need a negative slope. We need a positive slope. 27 So a can't be our best answer...