When written in vertex form, h= -1.5.
Hope this helps!
Edit:
Step 1: Group the first 2 terms together, separating them from the constant term.
Step 2: Factor out leading coefficient, for completing the square to work, the coefficient of x^2 must be 1.
Step 3: Complete the square, Take half of x coefficient and square it. Notice to keep equation balanced you must add this number and subtract it making the net effect zero.
Step 4: Distribute and add constants.
So x-(-1.5) is the "h" you're looking for.
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