The sum of 9 and twice a number

I need to write this as an algebraic equation.

The unknown number is n

Write 3.01 (1 repeating) as a mixed fraction?

Suppose the real exchange rate is 3/4 gallon of country A's gasoline per gallon of U. S. gasoline, a gallon of U. S. gasoline costs $3.00 U. S., and a gallon of gas in country A costs 6 units of their currency. What is the nominal exchange rate? a.

It takes chris 30 mininutes to walk to work it takes him 1/3 of the time to drivewhat is the latesest time he can drive to work and arrive at 8:00

How does f (x) = 6x change over the interval x = 3 to x = 4?

The number of vertices in a pyramid is equal to the number of faces. How many vertices does a regular pyramid with 40 edges have? Euler's formula: V + F = E + 2 A. 20 B. 21 C. 40 D. 42

A population of flies, P, over a given amount of time, x, is modeled by the expression P (1+r) ^x. Note: r represents percentage rate as a decimal What does each factor in the expression represent? Select each correct answer.

The elevators in the Empire State Building descend at a rate of about 7 meters per second. How far has the elevator descended after 10 seconds?

Tan154-tan49/1+tan154tan49 *all are in degrees. What does sin, cos, and tan equal?

What is the unit rate for this problem: $4.50 for 10 ounces of trail mix

the equation y=3x+7 shows the relationship between the number of days (x) and the number of stamps alex has collected (y). Predict the number of stamps he will have in 12 days.