Solve w= 1/2 x^2y for y

This is so hard and it’s for a test

What is the equation of this graphed line? enter your answer in slope-intercept form in the box.

Jamie went to home depot.she bought 25 bags of soil that cost $9 per bag.she bought 15 pots at $8 each,and she bought 23 bags of pebbles at $15 each.she used a coupon that gave her $5 off for every 100 dollars she spent.how much did jame pay at the end?