Find the value of x

brainlest for whoever answers!

also show work so i can understand

Monica build a remote control toy airplane for science project to test the plane she launched it from the top of a building the plane travel a horizontal distance of 50 feet before landing on the ground a quadratic function which models the height of the plane in feet relative to the ground at a horizontal distance of x feet from the building is shown

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Write a function rule for the table