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Completing the Square $x^2+bx+c\rightarrow \left(x-h\right)^2+k$

Fill in the blanks.

$x^2+12x+\square =\left(x+6\right)^2$

$x^2+8x+\square =\left(x+4\right)^2$

Fill in each blank. Separate your answers with a comma. For example:

$x^2+4x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2\quad$ Ans. $4,2$

$x^2+16x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2$

$x^2+12x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2$

$x^2+4x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2$

$x^2+6x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2$

Fill in the blanks.

$x^2-12x+\square =\left(x-6\right)^2$

$x^2-18x+\square =\left(x-9\right)^2$

Fill in each blank. Separate your answers with a comma. For example:

$x^2-6x+\boxed{ \text{A} } =\left(x- \boxed{ \text{B} }\,\right)^2\quad$ Ans. $9,3$

$x^2-6x+\boxed{ \text{A} } =\left(x-\boxed{ \text{B} }\,\right)^2$

$x^2-12x+\boxed{ \text{A} } =\left(x-\boxed{ \text{B} }\,\right)^2$

$x^2-16x+\boxed{ \text{A} } =\left(x-\boxed{ \text{B} }\,\right)^2$

$x^2-8x+\boxed{ \text{A} } =\left(x-\boxed{ \text{B} }\,\right)^2$

Fill in the blanks. Give your answer as an improper fraction.

$x^2-3x+\square =\left(x-\frac{3}{2}\right)^2$

$x^2+3x+\square =\left(x+\frac{3}{2}\right)^2$

Fill in each blank. Separate your answers with a comma. Give your answers as an improper fractions. For example:

$x^2-5x+\boxed{ \text{A} } =\left(x- \boxed{ \text{B} }\,\right)^2\quad$ Ans. $\frac{25}{4},\frac{5}{2}$

$x^2-7x+\boxed{ \text{A} } =\left(x-\boxed{ \text{B} }\,\right)^2$

$x^2+9x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2$

$x^2-5x+\boxed{ \text{A} } =\left(x-\boxed{ \text{B} }\,\right)^2$

$x^2+3x+\boxed{ \text{A} } =\left(x+\boxed{ \text{B} }\,\right)^2$
Now we will convert $f(x)=x^2+6x+7$ to the form $f(x)=\left(x-h\right)^2+k$.

$f(x)=x^2+6x+7$

$f(x)=x^2+6x\phantom{++|}+7$

$f(x)=x^2+6x+$ $+7-$

$\phantom{f(x)=\,}\underbrace{\phantom{x^2+6x+9}}_{\left(x+3\right)^2}$

$f(x)=\left(x+3\right)^2-$

$\phantom{}$

$\left(\text{move}+7\;\text{to the right}\right)$

$\left(\text{add and subtract}\right)$

$\phantom{}$

Write $f\left(x\right)=x^2-4x-3$ in the form $f\left(x\right)=\left(x-h\right)^2+k$.

$f(x)=x^2-4x-3$

$f(x)=x^2-4x\phantom{++|}-3$

$f(x)=x^2-4x+$ $-3-$

$\phantom{f(x)=\,}\underbrace{\phantom{x^2-4x-3}}$

$f(x)=\bigl(x-$ $\bigl)^2-$

$\phantom{}$

$\left(\text{move}-3\;\text{to the right}\right)$

$\left(\text{add and subtract}\right)$

$\phantom{}$

Write $f(x)=x^2+10x+11$ in the form $f(x)=\left(x-h\right)^2+k$.

$f(x)=x^2+10x+28$

$f(x)=x^2+10x\phantom{++|}+28$

$f(x)=x^2+10x+$ $+28-$

$\phantom{f(x)=\,}\underbrace{\phantom{x^2+10x+25}}$

$f(x)=\bigl(x+$ $\bigl)^2+$

$\phantom{}$

$\left(\text{move}+28\;\text{to the right}\right)$

$\left(\text{add and subtract}\right)$

$\phantom{}$

Write $f(x)=x^2+3x+5$ in the form $f(x)=\left(x-h\right)^2+k$. Give your answers as improper fractions.

$f(x)=x^2+3x+5$

$f(x)=x^2+3x\phantom{++|}+5$

$f(x)=x^2+3x+$ $+5-$

$\phantom{f(x)=\,}\underbrace{\phantom{x^2+3x+\frac{9}{4}}}$

$f(x)=\bigl(x+$ $\bigl)^2+$

$\phantom{}$

$\left(\text{move}+5\;\text{to the right}\right)$

$\left(\text{add and subtract}\right)$

$\phantom{}$

Practice

Write the following in the form $\left(x-h\right)^2+k$. Give your answers using improper fractions.

$x^2+2x-5$
$x^2+2x+5$

$x^2-2x+2$
$x^2-10x-3$

$x^2+3x-4$
$x^2+7x+3$

$x^2-3x-4$
$x^2-7x+5$