Answer:
The correct answer is actually around 21%. Are you sure the question wasn't asking what the approximate percent decrease from 85 to 70 was? Because in that case it would be around 17%.
Step-by-step explanation:
Answer:
Step-by-step explanation:
f(x,y)=10-x^2-y^2
To find derivative of z w.r.t. x is treat any other variable as a constant.
dz/dx=0-2x-0
dz/dx=-2x
Evaluating this at (7,-3) gives us dz/dx=-2(7)=-14.
Since this result is negative, it mrans as x increases z decreases.
f(x,y)=10-x^2-y^2
To find derivative of z w.r.t. y is treat any other variable as a constant.
dz/dx=0-0-2y
dz/dx=-2y
Evaluating this at (7,-3) gives us dz/dy=-2(-3)=6.
Since this result is positive it mrans as y increases z decreases.
Answer:
33 and 42
Step-by-step explanation:
Answer:
(8 / x) + (21 / y)
Step-by-step explanation:
Given that:
Average driving speed = x mph
Miles driven to work = 8 mile
Miles by train to work = 21 miles
Average train speed = y
Total time taken to get to work. :
Recall : time taken = distance / speed
Hence,
Time taken =) total distance / average driving speed)
Total time taken = (8 / x) + (21 / y) hours
Total time taken = (8 / x) + (21 / y) hours