When Harry arrived there were 20 lily pads. This can be interpreted as the function's y-intercept.
b= 20
Harry eats 4 lily pads an hour, which means for every 1 step to the right, the function moves 4 units in the negative vertical direction. This can be interpreted as a slope of m=- 4. Now we can write our function.
y=- 4x+20
Heinrick's Pond
Just like when we found the equation for the lily pads in Harry's pond, we can find an equation describing the lily pads in Heinrick's pond. Heinrick eats 7 lily pads an hour, and there are 29 lily pads to begin with. With this information, we can write an equation.
y=- 7x+29
Same Number of Lily Pads
We can determine when the number of lily pads are the same by setting the equations equal to each other and solving for x.
After three hours the ponds have the same number of lily pads.
b We know that after 3 hours the number of lily pads in the ponds are the same. Therefore, to determine the number of lily pads we substitute x=3 in one of the equations and evaluate.
