Answer:

Step-by-step explanation:
Line 1: (1, a) and (5, −2)
slope of the line is

Line 2: (2, 8) and (−5, a + 7)
slope of the line is

when the lines are parallel then slopes are equal

cross multiply it


subtract 4a from both sides


divide both sides by 3

Answer: I think 9
Step-by-step explanation:
Answer:
Using a graphing calc.
Step-by-step explanation:
Answer:
cm³/min
Step-by-step explanation:
Let h = height of water and r = radius of its surface

At all times,

So,



We want 

= -2 cm³/min



When h = 8 cm


cm³/min
The depth of the water is decreasing at a rate of
cm³/min
.