Why is there a plus or minus in the quadratic formula?

Md Ariful Islam

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Dr. Md Rushad Rahman

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When you take the square root of both sides of the equation, you need a plus or minus sign before the right side to show that the positive value squared equals (x+b/2a)² and that the negative value squared equals (x+b/2a)².The square root of x², for example, does not equal x but rather equals the absolute value of x, so the right side may be positive or negative.

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