Answer:
The correct answer is the last option, that is, 
Step-by-step explanation:
We have been given that the first runner has $112 in savings, received a $45 gift from a friend, and will save $25 each month. Therefore, amount of money in the account of first running after m months will be: 
We have been given that the second runner has $50 in savings and will save $60 each month. Therefore, amount of money in the account of second running after m months will be: 
In order for amount of money to be equal in accounts of both the runners, we set up:
Upon rewriting the left hand side using commutative law, we get:
Therefore, we can see that the last option is the correct answer.
For this case we have the following expression:
From here, we must clear the value of a.
We then have the following steps:
Place the terms that depend on a on the same side of the equation:
Do common factor "a":
Clear the value of "a" by dividing the factor within the parenthesis:
Answer:
The clear expression for "a" is given by:
The equation of the line would be y = (1/2)x.
To find the equation of a line that is reflected through the line y = x, we just switch the x and y. Then, solve for y.
y = 2x
x = 2y
0.5x = y
Corrected Question
The volume of air inside a rubber ball with radius r can be found using the function V(r) = four-thirds pi r cubed. What does V(5/7) represent?
Answer:
(B)the volume of the rubber ball when the radius equals five-sevenths feet
Step-by-step explanation:
The Volume of a sphere of radius r can be found using the formula:
Therefore comparing the expression: 
with V(r):
Thus, is the volume of a ball of radius 
feet.
The correct option is B.
Answer:
x = 5m/s
Step-by-step explanation:
Distance flying out = 12 km (headwind)
Distance flying back = 12 km (tailwind)
total distance = 12 + 12 =24 km
wind speed = 1km/h
speed going out (with headwind) = (x - 1) km/h
speed coming back (with tailwind) = (x + 1) km/h
Time taken to go out = distance going out / speed going out
= 12 / (x-1)
Time taken to come back = distance coming back / speed coming back
= 12 / (x+1)
total time = time taken to go out + time taken to come back
5 =[ 12/(x-1) ] + [ 12/(x-1)]
expanding this, we will get
5x² - 24x - 5 = 0
solving quadratic equation, we will get
x = -1/5 (impossible because speed cannot be negative)
or
x = 5 (answer)
