Ivanna works as a tutor for $10 an hour and as a waitress for $15 an hour. This month, she worked a combined total of 106 hours at her two jobs. Let t be the number of hours Ivanna worked as a tutor this month. Write an expression for the combined total dollar amount she earned this month.

Question

campbell_st · Answer

well you know the hours

t = tutor w = waitress

t + w = 106

making w the subject then its 

w = 106 - t

now for the pay 

pay = 10t + 15w

substitute the w value... w = 106 - t  into the equation above and you have
answer the question.