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 Question from Marie, a student: How to you convert the equation of a line from x-intercept form (y=(x-x1)(x-x2)) to general form (y=ax^2+bx+c) if it involves square roots? For example: Convert this equation to general form: y=(x+the square root of 5)^2 Thanks for the help!

Hi Marie,

I am sure that you know that

$\left( a + b \right)^2 = a^2 + 2ab + b^{2}.$

Try this expansion with

$\left( x + \sqrt{5} \right)^{2}.$

Write back if you need more assistance,
Penny

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