Forums → The Tavern → 4=5

I can't find a mistake in this...

-20=-20
16-36=25-45
4^2-9*4=5^2-9*5
4^2-9*4+81/4=5^2-9*5+81/4
(4-9/2)^2=(5-9/2)^2
4-9/2=5-9/2
4=5

...can you?