Answer:
the 21st day
Step-by-step explanation:
21 is 3 and 7's least common multiple
The polynomial remainder theorem says that the remainder when dividing a polynomial

by a linear divisor

is simply

.
If

, then the remainder upon dividing by

is

You could also verify this by actually computing the quotient and remainder.
31 students do their homework every night
Answer:
Light, Volume
Step-by-step explanation:
The volume of sound; the loudness or softness of a musical passage.
Simplify the first numerator first
-2(x+1)
-2x-2
Then you can set up an equation using cross multiplication
5(-2x-2)= 3x
Simplify and solve
-10x-10=3x
-10=13x
-10/13=x
Final answer: x=-10/13