Translate a algebraic expression .four less than four times a number. the translation is? type an expression using x as the variable.

Tim's phone service charges $23.06 plus an additional $0.22 for each text message sent per month. if tim's phone bill was $28.56, which equation could be used to find how many text messages, x, tim sent last month?

What is the value of x in the this question ?

Use sigma notation to represent the following series for 9 terms.