At a competition with 8 runners, 2 medals are awarded for first and second place. Each medal is different. How many ways are there to award the medals?

Can someone me and do the problem plz so i can understand it more better

What is the solution to this system of equations? y= 2x - 3.5 x - 2y = -14

Jessica is organizing a guided tour of the rain forest. the average profit per person that the touring company makes is given by the rational expression 18x+35/x, where x is the number of people going on the tour. what does the numerator of this rational expression represents?