Expert: Sherman D. - 4/13/2005

Question
I have 2 questions that I can't solve, each for a different reason:
1. 1/5(3x^2-10)=18x, write the equation in general form.My answer key says that the answer is 3x^2-90x-10, but I don't understand how they get that. Can you please exlain that to me.
2. Also, x^2+2ax+a^2, solve for x by factoring. By tis problem, they want me to solve for x while giving me a 2nd variable, a. I never earnt how to do that, especially through factoring. Please explain how to factor this as if I only had a pen and paper with me to do it. Thank you very much.

Answer
If by this you mean

1.)
(1/5)(3x^2 - 10)) = 18x
becomes
(3x^2 - 10)/5 = 18x
mulitply both sides by 5
3x^2 - 10 = 90x
subtract 90x from both sides
3x^2 - 90x - 10 = 0

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2.)
x^2 + 2ax + a^2
(x + a)(x + a)

just treat it like a x^2 + 2xy + y^2 problem.