Answer:
The percent increase is 74%
Step-by-step explanation:
Copy and Paste
Find the depth of the river at 9 hours and 18 hours by seeing where the line is on the Y axis.
At 9 hours the river is 18 feet deep
At 18 hours the river is 21 feet deep.
The average rate of change is the change in Y over the change in X
The Y is the depth and the X is the time:
(21-18) / (18-9) = 3/9 = 1/3 = 0.33
The average rate of change is 0.3 foot per hour. ( Rounded to nearest tenth)
Notice, 3 decimals, so, we can just use 3 zeros, thus
Move constant to other side
add 1
4c^2-8c=1
divide by 4 to make leading coeficient 1
c^2-2c=1/4
take 1/2 of linear coeficient and square it
-2/2=-1, (-1)^2=1
add that to both sides
c^2-2c+1=1/4+1
factor perfect squaer and add
(c-1)^2=5/4
square root both sides
c-1=+/-(√5)/2
add 1
c=1+/-(√5)/2
c=2.12 or -0.12
I think it will be because if you multiply 1/2 times 4/5 it will be 0.4