How to find a point on the line? x cordinate is given as x.

Question

The diagram is like a rectangle is inscribed in an isosceles right triangle whose hypotneus is 2 units long. AB is another side of the right triangle and P is a point on it(also a vertex of the rectangle). How do I find the cordinates of P(x,?)
A hint is given that I have to write equation of the line AB.

Answer 1

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