Please .. literally begging for someone to help me on all parts of this problem !

What is the value of x in the diagram below?

Solve for x and y: 217x + 131y = 913; 131x + 217y = 827

Marquise has 200 meters of fencing to build a rectangular garden. the garden's area (in square meters) as a function of the garden's width w w (in meters) is modeled by: a ( w ) = − w 2 + 1 0 0 w a(w)=−w 2 +100w what side width will produce the maximum garden area? meters