Question

A plant’s growth rate is observed and recorded for a science experiment. The observer notes that on week 2, the plant is 4 inches high. On week 5, the plant is 13 inches high.

Part A: Write an equation in point-slope form that could model the relationship between the week, x, and the height of the plant, y.

Answer 1

y - 13 = 3(x - 5)

Explanation:

x represents week and y represents inches. Week 2 and week 5 = 2 to 5 = three number difference. The inches which is 4 and 13 have a 9 inched difference. So like I said week represents x and y represent inches so now u have to find the slope, which would be y/x so replace it with the numbers we got so it would now be 9/3. The simplified version would be 3. So the slope is 3.

Point-slope equation: y-y^1=m(x-x^1), y^1 and x^1 are just some random points on the graph, but since we don't have a graph we can use either week 2 and 4 inches or week 5 and 13 inches because if this were a graph, those would be existing points on the graph. And m is the slope so just replace m with 3. We'll use 5 and 13 so: y - 13 = 3(x - 5)

side note: kinda took a long time sorry haha, I had to refresh my knowledge on point-slope equations since it's been a long time since i learned it.