signature – How to get Y from X

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Ok, so I get address generation now, and I understand that X is hashed, however for verification of a signature, we need the public point, (x,y)

How would one get Y from X?

Lets take an example, im gonna use my generator (0x79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798,0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8) and use private “10” (using a = 0, b = 7, p = 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f) to get:

(0xa0434d9e47f3c86235477c7b1ae6ae5d3442d49b1943c2b752a68e2a47e247c7,0x893aba425419bc27a3b6c7e693a24c696f794c2ed877a1593cbee53b037368d7)

Now we remove Y, to only have: 0xa0434d9e47f3c86235477c7b1ae6ae5d3442d49b1943c2b752a68e2a47e247c7

Meaning that we need to get Y from X, how would I do this? I never seen this explained really and everything I tried doesn’t result in the correct Y value



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