If Shane’s average number of jumps completed is greater than one-half, then the eighth graders earn 50 points. If not, the seventh graders earn 50 points. Which grade should be awarded 50 points?

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.

Where is the expression you want us to evaluate?

I  dont  know much about vertexes but i know to solve this function you need to use foil method and then corresponmd the vertex with the actual coordinates, hope i !