A linear function is one whose formula can be written in the form
Ax + By = C where A, B, C are real numbers and A, B are not both 0. (This is standard form, too.)

"Cross multiply."

Subtract 12.

Subtract 2y.

This matches up with standard form with A = 3, B = -2, C = -20.
It's a linear function.
Answer:
Your answer would be 5y=6
Hope this helps!
Answer:
Step-by-step explanation:
Formula = A=πr2
Putting values in the equation
A = (3.14) (5.52)^2
= 95.73
75 additional minutes were used
$61.20-$49.95=$11.25
$11.25/$0.15=75 additional minutes