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Question
Solve by completing the square 3x^2-8x-6=0.
3x^2 - 8x - 6 = 0
add 6 to both sides
3x^2 - 8x = 6
divide everything by 3
x^2 - (8/3)x = 2
divide (8/3) by 2, then square it, and add it to both sides
(8/(3 * 2))^2 = (8/6)^2 = (4/3)^2 = (16/9)
x^2 - (8/3) + (16/9) = 2 + (16/9)
x^2 - (8/3) + (16/9) = (18/9) + (16/9)
x^2 - (8/3) + (16/9) = (34/9)
put the left side into a perfect square
(x - (4/3))^2 = (34/9)
sqrt both sides
x - (4/3) = (sqrt(34))/3
add (4/3) to both sides
x = (4/3) ± (sqrt(34)/3)
or
x = (4 ± sqrt(34))/3
so
x = (4 + sqrt(34))/3
x = (4 - sqrt(34))/3
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Advanced Math
Answers by Expert:
Sherman D.
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I can answer questions dealing in mathematics of all kinds except for Physics and Calculus, but i can answer questions in Pre-Calculus and Chemistry. I can also answer questions in Recipes of all kinds. I can find games cheats/walkthroughs, but i can`t find a specific game online or offline. I can also do history and recipes for alcoholic beverages.
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Mathematics, Recipes, History, and Games.
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High School graduated. I graduated with honors, and i was in Beta Club for a year and a half.
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Principle's list and A and B honor roll in high school only.
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