Charlotte wishes to pay off her mortgage. She is willing to make payments of $1200 a month and has already paid $40,000 as a down payment. Write an equation that models the time it takes for Charlotte to pay her mortgage with C as the cost of the mortgage and M the numbers of months it will take.

Marco has $38.43 dollars in his checking account. his checking account is linked to his amazon music account so he can buy music. the songs he purchases cost $1.29. part 1: write an expression to describe the amount of money in his checking account in relationship to the number of songs he purchases. part 2: describe what the variable represents in this situation.