Answer:
The maximum number of songs that the symphonic choir can record is 14
Step-by-step explanation:
Let
x ----> the number of songs of the symphonic choir
we know that
The number of songs of the jazz choir multiplied by its average time per song plus the the number of songs of the symphonic choir multiplied by its average time per song, must be less than or equal to 72 minutes
so
The inequality that represent this situation is

solve for x

subtract 21 both sides

divide by 3.6 both sides

therefore
The maximum number of songs that the symphonic choir can record is 14
ANSWER
(C) d=1
EXPLANATION
The given equation is

Factor the first fraction to get,

Multiply through by (d+2)(d-4)

Expand:




divide both sides by -2

Answer:
This is an equation.
Step-by-step explanation:
An expression would mean that there is no equal sign, but since there is, that makes it an equation.