Answer:
Ok, this took some thinking... But the answer I came up with is w=(h-8/5)*5.
Explanation:
So w stands for the number of weeks and h stands for the height of the plant. And based on the first equation, to reverse it and find the number of weeks based on the height of the plant you have to work backwards. I started out with some points based on the first equation, I plugged in one week and I got that the plant would be 9/5 inches (I'll be using inches to make everything easier). So with that point, I can start creating the equation.
You would separate the w, or week by itself as that is the variable you are trying to find. So w=
Next, you want to work backwards from the first equation, you start with h and you subtract 8/5 from it as that is the original height of the plant and you don't want that to mess up with you multiplication of division later on. So, w=(h-8/5)
Finally, you can either divide by 1/5 or multiply by 5 , they both work the same for the equation. What that does is it gets rid of the fraction that is left over from the beginning, and gives you a whole number showing the number of weeks that it has taken the plant to grow. So the final equation is w=(h-8/5)*5 (or / 1/5)
Checking: To check the equation you just plug in the points, use any that you want from the first equation.
Here's week one: h=(1/5)*1 + 8/5, turning into h=9/5.
Then for the newly created equation: w=(9/5-8/5)*5
1/5 * 5 = 1, so w=1. That will work for any week number, just use the first equation to come up with your numbers.
Explanation: