Subtract seven more than twice a number from the square of 1/3 of the number to get zero

I think it would be -7 + 2x = 1/3x

Ithink if im not mistaking b is -3 but im not a 100% sude

This is what i found “an explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location). it defines the sequence as a formula in terms of n. this example is an arithmetic sequence(the same number, 5, is added to each term to get to the next term).” i hope this you for what your looking for. can you plz mark me brainliest?