Whats 100+500+200-300+1,893???

How do you use the elimination method for this question? explain, because i really want to understand!

You're locked out of your house. the only open window is on the second floor, 25 feet above the ground. there are bushes along the edge of the house, so you will need to place the ladder 10 feet from the house. what length ladder do you need to reach the window?

What is the solution to the system of equation graphed belowa.(0,-4)b.(2,5),1),-3)