How do you find the missing value to complete the square $x^{2} + 2 x$ $x^2+2x$ ?

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Answer 1 · 2015-05-30T17:29:54

${(x + a)}^{2} = x^{2} + 2 a x + a^{2}$ $(x+a)^2 = x^2+2ax+a^2$

We want $2 a x$ $2ax$ to match $2 x$ $2x$ , so $a = 1$ $a=1$ and the missing value is $a^{2} = 1^{2} = 1$ $a^2 = 1^2 = 1$

$x^{2} + 2 x + 1 = {(x + 1)}^{2}$ $x^2+2x+1 = (x+1)^2$

How do you find the missing value to complete the square x2+2xx^2+2x?