Answer:
A
Step-by-step explanation:
When you read the question it says that her average speed from the library to the gym is 15 mph less than her speed from her home to the library. So x - 15 is what describes that situation.
If it is A it cannot be anything else.
B is incorrect. x - 15 is not a time. It is a rate. It can be used to develop the amount of time, but by itself it is still A.
C is incorrect. Her average speed from her house to the library is x
D is incorrect. The distance is given as the same as from her home to the library as from the library to the gym. Both are 4
Answer:
Step-by-step explanation:
Rationalize the denominator of b. So, multiply the numerator and denominator by 

Now, find a +b

Combine like terms

Now find (a + b)²
(a +b)² = 

Hint: 
Answer:
It would roll in this direction.

Step-by-step explanation:
It would roll to the direction of maximum decrease, which is the -1 times the direction of maximum increase, which is given by the gradient of the function.
Since

For this case, the gradient of your function would be

And -1 times the gradient of your function would be

Then, at

So it would go towards

The magnitud of that vector is

and to conclude it would roll in this direction.

Answer:
48 cubes
Step-by-step explanation:
step 1
Find the volume of one 1/2 unit cube
The volume of the cube is given by

where
b is the length side of the cube
we have

substitute


step 2
Divide the volume of the prism by the volume of one cube
