The square's diagonal is the triangle's hypotenuse.
the original Pythagorean theorem is

where
a and
b are the two sides and
c is the hypotenuse.
that means the Pythagorean theorem for this question is:

or
Take half of the coefficient on the x term
Answer:
sorry the diagram is not clear......
Answer:
(16.5 + 1.5n)° = (12 + 2n)° [given]
=> 16.5 – 12 = 2n – 1.5n
=> 4.5 = 0.5n
=> n = 4.5/0.5
=> n = 9