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Select the correct answer.What is the solution to the equation?(1 - 2)2 + 4 = 1-Ο Α.-3 and -6OB.3 and 6O C. -3OD. 6ResetNext

Select the correct answer.What is the solution to the equation?(1 - 2)2 + 4 = 1-Ο Α.-3 and-example-1
User Daly
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1 Answer

2 votes

Given the equation:


\mleft(x-2\mright?^{})^{(1)/(2)}+4=x

1. You need to remember the following property:


\sqrt[n]{b^m}=b^{(m)/(n)}

2. Then, you can rewrite the equation as follows:


\sqrt[]{x-2}^{}+4=x

3. Now you need to apply the Subtraction Property of Equality by subtracting 4 from both sides of the equation:


\begin{gathered} \sqrt[]{x-2}^{}+4-(4)=x-(4) \\ \\ \sqrt[]{x-2}^{}=x-4 \end{gathered}

4. Square both sides of the equation:


\begin{gathered} (\sqrt[]{x-2})^{}=(x-4)^2 \\ x-2=(x-4)^2 \end{gathered}

5. Apply the following on the right side:


(a-b)^2=a^2-2ab+b^2

Then:


\begin{gathered} x-2=(x^2-2(x)(4)+4^2) \\ \\ x-2=x^2-8x+16 \end{gathered}

6. Write the Quadratic Equation in this form:


ax^2+bx+c=0

Then:


\begin{gathered} 0=x^2-8x+16-x+2 \\ x^2-9x+18=0 \end{gathered}

7. In order to factor it, you can find two numbers whose sum is -9 and whose product is 18. These numbers would be -3 and -6. Then:


(x-3)(x-6)=0

8. Notice that you get these values of "x":


\begin{gathered} x-3=0\Rightarrow x_1=3 \\ \\ x-6=0\Rightarrow x_2=6_{} \end{gathered}

9. Substitute each value of "x" into the equation and evaluate, in order to check if they are solutions to the equation:

- For:


x_1=3

You get:


\begin{gathered} \sqrt[]{(3)-2}^{}+4=(3) \\ \sqrt[]{1}^{}+4=3 \\ 5=3\text{ (False)} \end{gathered}

It is not a solution.

- For:


x_2=6

You get:


\begin{gathered} \sqrt[]{(6)-2}^{}+4=(6) \\ \sqrt[]{4}+4=6 \\ 2+4=6 \\ 6=6\text{ (True)} \end{gathered}

It is a solution.

Hence, the answer is:

User Jordan Ell
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