Find the slope of the line that passes through 8,4 and 3,1

Cassie is traveling 675 miles today to visit her brother and his family. so far, she has stopped for gas three times. at the first stop, she put in 7.1 gallons of gas and paid $23.79. at her second stop, she put in 5.8 gallons of gas and paid $19.08. and, at the third stop, 6.6 gallons and paid $20.39. at which stop did casey pay the most for gas?

The graph is supposed to show f(x) = 3 sin (x/4+1) - 1/2. which of the following are correctly represented in the graph? select two of the following that apply.

Can anyone me get through my algebra 2 class? the only class i need to graduate..