Y - 5 = 3 - 9(y + 2)
Expand the brackets
y - 5 = 3 - 9y + 18
Move y to one side, and constants to the other
10y = 26
Solve for y
y = (26 / 10) = 2.6
It would not be an exact amount of quarters, but you would need 7 quarters in total to dry your clothes for 45 minutes. All you have to do is divide 45 by 7, which is roughly 6.42 quarters.
Answer:
1/20 of 2 minutes = 6 seconds
I don’t even know 5x 15 equals 7 because 12inches is a feet
Formula for Riemann Sum is:

interval is [1,3] so a = 1, b = 3
f(x) = 3x , sub into Riemann sum

Continue by simplifying using properties of summations.

Now you have an expression for the summation in terms of 'n'.
Next, take the limit as n-> infinity.
The limit of

goes to 0, therefore the limit of the summation is 12.
The area under the curve from [1,3] is equal to limit of summation which is 12.