## What's wrong with this? (basic algebra)

For the discussion of math. Duh.

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### What's wrong with this? (basic algebra)

I was suspecting the completing the square step, but that checks out, and I can't see any other sneakiness.
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### Re: What's wrong with this? (basic algebra)

it's the part where they take the square root of both sides. 4-9/2 = -1/2, and 5-9/2 = 1/2. -(1/2)^2 = (1/2)^2, but -.5 != .5

t1mm01994

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### Re: What's wrong with this? (basic algebra)

t1mm01994 wrote:it's the part where they take the square root of both sides. 4-9/2 = -1/2, and 5-9/2 = 1/2. -(1/2)^2 = (1/2)^2, but -.5 != .5

Slight typo there. Should read (-1/2)^2 = (1/2)^2
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### Re: What's wrong with this? (basic algebra)

Sigh. The answer is *always* "the part where they take the square root of both sides".
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### Re: What's wrong with this? (basic algebra)

nah, I know several from the type "the part where they divide by 0".. Or with a > rather than a = in which the clue is "the part where they divide by a negative number".

t1mm01994

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