I don’t know what to do

Find the domain and range of the following function f(x) = 51x - 21+ 4

You are living in aldine, tx and you are planning a trip to six flags in arlington, tx. you look on a map that has a scale of 0.5 inches to 30 miles. if the map shows the scale distance from aldine to arlington is 4 inches, how far is the actual distance?

Gabrielle's age is three times mikhail's age. the sum of their ages is 40 . what is mikhail's age? __ years old