Can someone please help me on this?

The vertices of a triangle are a(7,5), b(4,2), c(9,2). what is m

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.

Which equation represents the function on the graph?