I need to know.
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All the answers are correct.
but its also better to use the quadratic formula if you can't cut b evenly in completing the square. so you don't have to deal with fractions.
but its also better to use the quadratic formula if you can't cut b evenly in completing the square. so you don't have to deal with fractions.
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I take it you have a quadratic that you want to factorize in order to find the zeros (x-intercepts) of a function.
You would use quadratic formula if you have exhausted all other options (because it is lengthy and takes time). You cannot use it when there are NO zeros because the Square Root will break and give you an imaginary number.
You generally should use completing the square because it's quick and easy and won't break (just becomes difficult to factorize).
You would use quadratic formula if you have exhausted all other options (because it is lengthy and takes time). You cannot use it when there are NO zeros because the Square Root will break and give you an imaginary number.
You generally should use completing the square because it's quick and easy and won't break (just becomes difficult to factorize).
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you can always use either, but it may be difficult to use completing the sqaure if b is not divisble by 2, or a radical or anything like that so the quadratic may be quicker
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quadratic formula to find the zeros.
complete the square to find the vertex.. or max value or min
complete the square to find the vertex.. or max value or min