Question 1041956
{{{3x^2-9x-12=0}}}
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Divide by 3
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{{{x^2 - 3x - 4 = 0}}}
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{{{x^2 - 3x = 4}}}
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Add (b/2a)^2 to each side
{{{x^2 - 3x + 9/4= 4 = 9/4 = 25/4}}}
{{{(x - 3/2)^2 = 25/4}}}
Can you finish?