At hour 9 the river is 18 feet deep.
At hour 18 the river is 21 feet deep.
From 9 to 18 hours is 9 hours difference.
From 18 to 21 feet is a 3 foot difference.
The average rate of change is the change in depth divided by the change in time:
3 feet / 9 hours = 0.3 feet per hour. ( Rounded to the nearest tenth)
72 I am guessing because you divide by 3
25 because you do 19 squared plus 16 squared equals 617, you do 617 rooted. It’s called pythagorus.
Answer:
x = 51
Step-by-step explanation:
39+12= 51