The sum of 9 and twice a number

i need to write this as an algebraic equation.

the unknown number is n

Find the constant of variation for the relation and use it to write an equation for the statement. then solve the equation.

Pyramid shown has a square base that is 18 inches on each side has a surface area of 164 square inches what is the slant height

Which statement accurately explains whether a reflection over the y axis and a 270° counterclockwise rotation would map figure acb onto itself?