SOLUTION: "what is the value of x?" 2x² + 12x + 15 = 0

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Question 552957: "what is the value of x?"
2x² + 12x + 15 = 0
Answer by AnlytcPhil(1806) About Me  (Show Source):
You can put this solution on YOUR website!
2x² + 12x + 15 = 0

Compare to

ax² + bx + c = 0

a=2, b=12, c=15

Substitute in

x = %28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ 

x = %28-%2812%29+%2B-+sqrt%28+%2812%29%5E2-4%2A%282%29%2A%2815%29+%29%29%2F%282%2A%282%29%29+

x = %28-12+%2B-+sqrt%28144-120+%29%29%2F4+

x = %28-12+%2B-+sqrt%2824%29%29%2F4+

x = %28-12+%2B-+sqrt%284%2A6%29%29%2F4+

x = %28-12+%2B-+2%2Asqrt%286%29%29%2F4+

x = %282%28-6+%2B-+sqrt%286%29%29%29%2F4+

x = %28-6+%2B-+sqrt%286%29%29%2F2+

Two solutions: %28-6+%2B+sqrt%286%29%29%2F2+ and %28-6+-+sqrt%286%29%29%2F2+

Edwin