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Completing the Square

Completing the Square 1.7 - Solution

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We want to complete the square for the given expression. To do so, we will first identify b.b. In a quadratic trinomial, bb is the linear coefficient, which is the number that is multiplied by the x-x\text{-}variable. x24x+c\begin{gathered} x^2-4x+c \end{gathered} Now, we will calculate (b2)2.\left(\frac{b}{2}\right)^2. Since we have that b=-4,b=\text{-}4, we can calculate the value of (b2)2\left(\frac{b}{2}\right)^2 by substituting -4\text{-}4 for b.b.
(b2)2\left(\dfrac{b}{2}\right)^2
(-42)2\left(\dfrac{{\color{#0000FF}{\text{-}4}}}{2}\right)^2
(-2)2(\text{-}2)^2
44
The number that completes the square is c=4.c=4. x24x+4\begin{gathered} x^2-4x+4 \end{gathered}