We need to solve for R, This is really simple.
The original expression is:
R (r1 + r2) = r1r2
To solve for a certain variable, we need to get this variable alone on one side of the equation and equate it with the other side.
In the given expression, to get R alone on one side we have to eliminate (r1 + r2).
In order to do this, we will divide both sides by (r1 + r2).
Doing this, we get the solution as follows:
R = (r1r2) / (r1 + r2)
3x = 6y
to get this into slope-intercept form, you simply need to solve for y. remember that slope-intercept form is y = mx + b, where m is your slope and b is your y-intercept.
3x = 6y ... divide both sides by 6
1/2x = y
y = 1/2x is your equation in slope-intercept form. because no "b" value is present, your intercept will simply be 0.
All you have to do is move your decimal point over eight places to the right and then subtract that from the first number and you have your answer.
Use Law of Cooling:

T0 = initial temperature, TA = ambient or final temperature
First solve for k using given info, T(3) = 42

Substituting k back into cooling equation gives:

At some time "t", it is brought back inside at temperature "x".
We know that temperature goes back up to 71 at 2:10 so the time it is inside is 10-t, where t is time that it had been outside.
The new cooling equation for when its back inside is:

Solve for x:

Sub back into original cooling equation, x = T(t)

Solve for t:

This means the exact time it was brought indoors was about 2.5 seconds before 2:05 PM
Answer:
the answer is 9.9997 ft
Step-by-step explanation:
the equation to find the radius is
r = √(3v / πh)