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Sole the quadratic equation by completing the square. x^2-14x+46=0Choose the appropriate form and fill in the blanks with the correct numbers. Then solve the equation. If there’s more than one solution, separate them with commas.

Sole the quadratic equation by completing the square. x^2-14x+46=0Choose the appropriate-example-1
User Hamish Downer
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1 Answer

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14 votes

SOLUTION

Write out the quadratic equation


x^2-14x+46=0

To solve by Completing the square, we apply the following steps

Step1: Take the constant term to the other side


x^2-14x=-46

Step2: Get half of the coefficient of x


\begin{gathered} Co-\text{efficient of x =14} \\ \text{ Half of the co}efficient\text{ of x=}\frac{\text{14}}{2}=7 \end{gathered}

Step3: Square the result in step 2 and add it to the equation in the equation in step1


x^2-14x+7^2=-46+7^2

Step4: Factorize the left-hand side and simplify the right-hand side of the equation in step 3


\begin{gathered} (x-7)^2=-46+49 \\ (x-7)^2=3 \end{gathered}

Step5: take the square root of both sides


\begin{gathered} \sqrt[]{(x-7)^2}=\sqrt[]{3} \\ x-7=\pm\sqrt[]{3} \end{gathered}

Hence the value of x is


\begin{gathered} x=7\pm\sqrt[]{3} \\ \text{Then the two values of x are } \\ x=(7+\sqrt[]{3}),(7-\sqrt[]{3})_{} \end{gathered}

User Vikram Thakur
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