Answer:
Step-by-step explanation:
We will let the x coordinates be the temp and the y coordinates by the number of chirps. Our coordinates then will look like this:
(60, 84) and (85, 184). If this is linear, then first we will find the slope of the line which will tell us, in the context of this problem, how many chirps a cricket gives per 1 degree of temp increase.
The slope formula is:
and filling in our numbers:
This means that for every 1 degree temp increase, a cricket will give 4 chirps. That's the m value in y = mx + b. Now we will pick one of the coordinates, doesn't matter which one, and use those x and y values in the point-slope form of a line to get the equation. I will choose (60, 85), just because. Using the other point will give you the exact same line equation, I PROMISE!
Using 85 as y1 and 60 as x1 in
y - y1 = m(x - x1) gives us
y - 85 = 4(x - 60) and
y - 85 = 4x - 240 and
y = 4x - 240 + 85 and
y = 4x - 155