According to modern math, it is 9 according to pre1917 math, it’s 1. Either way, the one on the left of ur image is the way it is written today, and should not be ambiguous because again 1917The problem is this question is too vague. The question itself should've been either of these:
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However flawed questions aside as everyone's been saying your method while not completely incorrect isn't what modern math standards define as correct.
Also you're right math doesn't simply change however since humans make math and define mathematical standards which are subject to error we can change what we know about math and fix errors that were once considered correct.