"factor the left hand side as a square for (x^2)+(x/2)+(1/16)=(9/16)"
If the left-hand side factors as a square it must have the form (x + k)2
Expand this to get x2 + 2kx + k2 which must match x2 + x/2 + 1/16
Look at the coefficients of x. To match we must have 2k = 1/2 or k = 1/4.
Look at the constant term. To match we must have k2 = 1/16. Since (1/4)2 does indeed equal 1/16 we have consistency.
So (x + 1/4)2 = 9/16
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