Have you come across this proof of the Pythagoras Theorem?

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I have come across many proofs of Pythagoras theorem like these - enter image description here

But today when i was trying different methods of proving the pythagorean theorem i found a way to prove it. But the construction is so simple and obvious so I wanted to check if this proof is there somewhere - enter image description here

Consider this right triangle with $\angle B = 90°$

$\Rightarrow △ABC \sim △ADB \Rightarrow \dfrac{AB}{AD}=\dfrac{AC}{AB} \Rightarrow AB^2=AC.AD \cdots (I)$

Similarly ,

$△ABC \sim △BDC \Rightarrow \dfrac{BC}{DC}=\dfrac{AC}{BC} \Rightarrow BC^2=AC.DC \cdots (II)$

Adding $(I) , (II) \Rightarrow AB^2+BC^2=AC(AD+DC)=AC^2$. Hence Proved.

A proof so simple yet I never came across it...