x2 -15x = -3
Make the left-hand side a perfect square by adding (-15/2)2.Add this to the right-hand side so as not to change the value.
This gives x2 -15x + (-15/2)2 = -3 + (-15/2)2
Or ( x- 7.5)2 = -3 +56.25
v(( x- 7.5)2) = v(-3+56.25 )
X -7.5 = ± 7.30
X = ± 7.30 + 7.5
jeffzod answered the question on December 20, 2017 at 13:08
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