Which expression is equivalent to 5y^-3

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?

Which coefficient matrix represents a system of linear equations that has a unique solution ? options in photo*

If t8 = 4 and t12 = −2, find the first three terms of the arithmetic sequence.