[Video] Q8: The table lists selected values of sam’s walking speed, in kilometers per hour (km/h), and his corresponding pulse, in beats per minute (bpm). there is a linear relationship between sam’s speed, x, and his pulse, f(x). which of the following equations describes f(x)?

Explanation for Question 8 From the Math (Calc) Section on the 2020 March Sat

So now we're looking at question number eight, which gives us a table where 2 we're told that the speed is our X values and the pulses are F 3 of X values. And F of X is just a fancy way to say 4 why. So really what's happening is our speed is still our X. 5 And then our pulse is going to be our Y values. 6 And now they want us to write a linear equation that shows the relationship 7 between our X and our Y. And whenever we do this, 8 odds are you're going to be using a M Y an equation 9 that is in slope intercept form. Right? 10 And so if you're using slope intercept form, you have to have an M, 11 which is going to be your slope, which would be all of these values 12 up here. And then also a B, which is going to be your Y 13 intercept, which is right here. 14 Right? And so with those in mind, we know that in order to find 15 our answer choice, we should either find the slope, the Y intercept or both. 16 And now we'll be most strategic way to do this question would be to 17 only find the slope, because if we look closely at all of our answer 18 choices, each one has a different slope. 19 So if I find the slope, there will only be one answer choice with 20 that slope. And then that will be my correct answer. 21 Now to find my slope, I need to pick two points. 22 Now, it doesn't matter which two points I pick, but I generally like to 23 use the lower numbers because lower numbers are easier to work with. 24 And I'll use those two points to solve for our slope, 25 which is M an...