Evaluating expressions

Given abcd ac=38 and ae=3x+4 find the value of x

Use the data on the dot plot to answer the question. how many people read for more than three hours last week? i'm on a unit test review

Tim's phone service charges $26.39 plus an additional $0.21 for each text message sent per month. if tim's phone bill was $31.64, which equation could be used to find how many text messages, x, tim sent last month?