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# Algebra/One More Math Question (12.7-2)

Question
Solve the system:
y = x^2 + 5x + 4
y = 8x + 8

Thank you very much for your time and assistance!

Take y = 8x + 8 and put into the 1st question.
This gives 8x + 8 = x² + 5x + 4.
Subtracting 8x + 8 from both sides gives 0 = x² - 3x - 4.
The quadratic equation has the square-root of (9-12) = sqrt(-3) in it.

The complete answer is x = (3ħsqrt(-3))/2.
Put that in y = 8x + 8 to get y.
That gives two possible choices for y, since the plus or minus gives two choices for x.
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 Rating(1-10) Knowledgeability = 10 Clarity of Response = 7 Politeness = 10 Comment Very helpful response.

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Algebra

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#### Scott A Wilson

##### Expertise

Any algebraic question you've got. That includes question that are linear, quadratic, exponential, etc.

##### Experience

I have solved story problems, linear equations, parabolic equations. I have also solved some 3rd order equations and equations with multiple variables.

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Documents at Boeing in assistance on the manufacturiing floor.

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MS at math OSU in mathematics at OSU, 1986. BS at OSU in mathematical sciences (math, statistics, computer science), 1984.

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Both my BS and MS degrees were given with honors.

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Students in a wide variety of areas since the 80's; over 1,000 of them have been in algebra.