What Is The Solution To The Equation X 2 + 2 X − 25 = X + 5 \sqrt{x^2+2x-25}=\sqrt{x+5} X 2 + 2 X − 25 ​ = X + 5 ​ ? Assume The Range Is All Real Numbers.A. X = − 6 X=-6 X = − 6 B. X = 5 X=5 X = 5 C. X = 6 , X = − 5 X=6, X=-5 X = 6 , X = − 5 D. X = − 6 , X = 5 X=-6, X=5 X = − 6 , X = 5

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Introduction

Solving equations involving square roots can be a challenging task, especially when the equation involves a quadratic expression inside the square root. In this article, we will explore the solution to the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5}, assuming the range is all real numbers.

Understanding the Equation

The given equation is x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5}. To solve this equation, we need to first simplify the expressions inside the square roots. We can start by factoring the quadratic expression x2+2x25x^2+2x-25.

Factoring the Quadratic Expression

The quadratic expression x2+2x25x^2+2x-25 can be factored as (x+5)(x5)(x+5)(x-5). Therefore, the equation becomes (x+5)(x5)=x+5\sqrt{(x+5)(x-5)}=\sqrt{x+5}.

Simplifying the Equation

Since the square root of a product is equal to the product of the square roots, we can simplify the equation as x+5x5=x+5\sqrt{x+5}\sqrt{x-5}=\sqrt{x+5}. We can cancel out the common factor x+5\sqrt{x+5} from both sides of the equation, assuming that x+50x+5 \neq 0.

Canceling Out the Common Factor

After canceling out the common factor x+5\sqrt{x+5}, the equation becomes x5=1\sqrt{x-5}=1. To solve for xx, we need to square both sides of the equation.

Squaring Both Sides

Squaring both sides of the equation x5=1\sqrt{x-5}=1 gives us x5=1x-5=1. We can add 5 to both sides of the equation to solve for xx.

Solving for xx

Adding 5 to both sides of the equation x5=1x-5=1 gives us x=6x=6. Therefore, one possible solution to the equation is x=6x=6.

Checking the Solution

To check if x=6x=6 is a valid solution, we need to substitute it back into the original equation. Substituting x=6x=6 into the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5} gives us 62+2(6)25=6+5\sqrt{6^2+2(6)-25}=\sqrt{6+5}, which simplifies to 36+1225=11\sqrt{36+12-25}=\sqrt{11}, and further simplifies to 23=11\sqrt{23}=\sqrt{11}. Since 2311\sqrt{23} \neq \sqrt{11}, x=6x=6 is not a valid solution.

Revisiting the Equation

Since x=6x=6 is not a valid solution, we need to revisit the equation and find the correct solution. We can start by re-examining the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5}.

Re-examining the Equation

The equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5} can be rewritten as (x+5)(x5)=x+5\sqrt{(x+5)(x-5)}=\sqrt{x+5}. We can simplify this equation by canceling out the common factor x+5\sqrt{x+5} from both sides of the equation.

Canceling Out the Common Factor

After canceling out the common factor x+5\sqrt{x+5}, the equation becomes x5=1\sqrt{x-5}=1. To solve for xx, we need to square both sides of the equation.

Squaring Both Sides

Squaring both sides of the equation x5=1\sqrt{x-5}=1 gives us x5=1x-5=1. We can add 5 to both sides of the equation to solve for xx.

Solving for xx

Adding 5 to both sides of the equation x5=1x-5=1 gives us x=6x=6. However, we already know that x=6x=6 is not a valid solution. Therefore, we need to find another solution.

Finding Another Solution

To find another solution, we can re-examine the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5}. We can start by squaring both sides of the equation.

Squaring Both Sides

Squaring both sides of the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5} gives us x2+2x25=x+5x^2+2x-25=x+5. We can simplify this equation by combining like terms.

Simplifying the Equation

Combining like terms in the equation x2+2x25=x+5x^2+2x-25=x+5 gives us x2+x30=0x^2+x-30=0. We can factor this quadratic equation as (x+6)(x5)=0(x+6)(x-5)=0.

Factoring the Quadratic Equation

The quadratic equation x2+x30=0x^2+x-30=0 can be factored as (x+6)(x5)=0(x+6)(x-5)=0. Therefore, the solutions to the equation are x=6x=-6 and x=5x=5.

Checking the Solutions

To check if x=6x=-6 and x=5x=5 are valid solutions, we need to substitute them back into the original equation. Substituting x=6x=-6 into the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5} gives us (6)2+2(6)25=6+5\sqrt{(-6)^2+2(-6)-25}=\sqrt{-6+5}, which simplifies to 361225=1\sqrt{36-12-25}=\sqrt{-1}, and further simplifies to (1)=1\sqrt{(-1)}=\sqrt{-1}. Since (1)=1\sqrt{(-1)}=\sqrt{-1}, x=6x=-6 is a valid solution. Substituting x=5x=5 into the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5} gives us 52+2(5)25=5+5\sqrt{5^2+2(5)-25}=\sqrt{5+5}, which simplifies to 25+1025=10\sqrt{25+10-25}=\sqrt{10}, and further simplifies to 10=10\sqrt{10}=\sqrt{10}. Since 10=10\sqrt{10}=\sqrt{10}, x=5x=5 is a valid solution.

Conclusion

In conclusion, the solutions to the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5} are x=6x=-6 and x=5x=5. Therefore, the correct answer is D. x=6,x=5x=-6, x=5.

Final Answer

The final answer is D. x=6,x=5x=-6, x=5.

Introduction

In our previous article, we explored the solution to the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5}. We found that the solutions to the equation are x=6x=-6 and x=5x=5. In this article, we will answer some frequently asked questions about the solutions to the equation.

Q: What is the range of the solutions to the equation?

A: The range of the solutions to the equation is all real numbers.

Q: How did you find the solutions to the equation?

A: We found the solutions to the equation by first simplifying the expressions inside the square roots. We then canceled out the common factor x+5\sqrt{x+5} from both sides of the equation. After that, we squared both sides of the equation to solve for xx.

Q: Why did you square both sides of the equation?

A: We squared both sides of the equation to eliminate the square root. This allowed us to solve for xx.

Q: What if the equation had been x2+2x25=x+5\sqrt{x^2+2x-25}=-\sqrt{x+5}?

A: If the equation had been x2+2x25=x+5\sqrt{x^2+2x-25}=-\sqrt{x+5}, we would have had to consider the case where x+50x+5 \leq 0. In this case, the equation would have become x2+2x25=x+5\sqrt{x^2+2x-25}=-\sqrt{x+5}, which would have led to the solutions x=6x=-6 and x=5x=5.

Q: Can you explain why x=6x=6 is not a valid solution?

A: x=6x=6 is not a valid solution because when we substitute x=6x=6 into the original equation, we get 62+2(6)25=6+5\sqrt{6^2+2(6)-25}=\sqrt{6+5}, which simplifies to 36+1225=11\sqrt{36+12-25}=\sqrt{11}, and further simplifies to 23=11\sqrt{23}=\sqrt{11}. Since 2311\sqrt{23} \neq \sqrt{11}, x=6x=6 is not a valid solution.

Q: Can you explain why x=6x=-6 and x=5x=5 are valid solutions?

A: x=6x=-6 and x=5x=5 are valid solutions because when we substitute x=6x=-6 and x=5x=5 into the original equation, we get (6)2+2(6)25=6+5\sqrt{(-6)^2+2(-6)-25}=\sqrt{-6+5} and 52+2(5)25=5+5\sqrt{5^2+2(5)-25}=\sqrt{5+5}, respectively. These equations simplify to 361225=1\sqrt{36-12-25}=\sqrt{-1} and 25+1025=10\sqrt{25+10-25}=\sqrt{10}, respectively. Since (1)=1\sqrt{(-1)}=\sqrt{-1} and 10=10\sqrt{10}=\sqrt{10}, x=6x=-6 and x=5x=5 are valid solutions.

Q: Can you provide more examples of equations that involve square roots?

A: Yes, here are a few examples of equations that involve square roots:

  • x24x+4=x2\sqrt{x^2-4x+4}=\sqrt{x-2}
  • x2+6x+9=x+3\sqrt{x^2+6x+9}=\sqrt{x+3}
  • x22x15=x5\sqrt{x^2-2x-15}=\sqrt{x-5}

Q: How do you solve equations that involve square roots?

A: To solve equations that involve square roots, you can start by simplifying the expressions inside the square roots. You can then cancel out any common factors and square both sides of the equation to solve for xx.

Conclusion

In conclusion, we have answered some frequently asked questions about the solutions to the equation x2+2x25=x+5\sqrt{x^2+2x-25}=\sqrt{x+5}. We have also provided some examples of equations that involve square roots and explained how to solve them.

Final Answer

The final answer is D. x=6,x=5x=-6, x=5.