Does this ever end? all appreciated

Step-by-step explanation:

According to Pythagoras Theorem a² + b² = c²

And the questio is having a right triangle in it so,

(Height of the building)² + (Length of the shadow)² = (The distance from the top of the building to the tip of the shadow)²

⇒ a² + (12)² = (20)²

⇒ a² = (20)² - (12)²

⇒ a² = 400 - 144

⇒ a² = 256

⇒ a = √256

⇒ a = 16

a^2+b^2=c^2

a=x

b=12

c=20

12 squared is 144

20 squared is 400

400-144=256

The square root of 256 is 16.

x=16

answer: all the values are within because it has a pattern that repeats from -6 to 4.

good luck!