Given That The Solutions To $x^2-x-26=-6$ Are $x=5$ And \$x=-4$[/tex\], Which Is A Reasonable Solution To The Inequality $x^2-x-26\ \textgreater \ -6$?A. $-4\ \textless \ X\ \textless \ 5$ B.

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Introduction

When solving inequalities, it's essential to understand the relationship between the solutions of the corresponding equation and the inequality. In this article, we will explore how to find a reasonable solution to the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6, given that the solutions to the equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6 are x=5x=5 and x=βˆ’4x=-4.

Understanding the Relationship Between Equations and Inequalities

To solve the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6, we need to understand the relationship between the solutions of the corresponding equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6 and the inequality. The equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6 has two solutions, x=5x=5 and x=βˆ’4x=-4. These solutions are the points where the graph of the equation intersects the x-axis.

Graphing the Equation

To visualize the relationship between the equation and the inequality, let's graph the equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6. We can rewrite the equation as x2βˆ’xβˆ’20=0x^2-x-20=0. This is a quadratic equation that can be factored as (xβˆ’5)(x+4)=0(x-5)(x+4)=0. The graph of the equation is a parabola that intersects the x-axis at x=5x=5 and x=βˆ’4x=-4.

Understanding the Inequality

The inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6 is a quadratic inequality that can be rewritten as x2βˆ’xβˆ’20>0x^2-x-20 > 0. This inequality is true for values of xx that make the quadratic expression positive. To find the values of xx that satisfy the inequality, we need to find the intervals where the quadratic expression is positive.

Finding the Intervals

To find the intervals where the quadratic expression x2βˆ’xβˆ’20x^2-x-20 is positive, we need to find the roots of the equation x2βˆ’xβˆ’20=0x^2-x-20=0. The roots of the equation are x=5x=5 and x=βˆ’4x=-4. These roots divide the number line into three intervals: (βˆ’βˆž,βˆ’4)(-\infty, -4), (βˆ’4,5)(-4, 5), and (5,∞)(5, \infty).

Testing the Intervals

To determine which intervals satisfy the inequality x2βˆ’xβˆ’20>0x^2-x-20 > 0, we need to test each interval by substituting a test value into the quadratic expression. Let's test each interval:

  • For the interval (βˆ’βˆž,βˆ’4)(-\infty, -4), let's choose a test value x=βˆ’5x=-5. Substituting x=βˆ’5x=-5 into the quadratic expression, we get (βˆ’5)2βˆ’(βˆ’5)βˆ’20=25+5βˆ’20=10(-5)^2-(-5)-20=25+5-20=10. Since 10>010>0, the interval (βˆ’βˆž,βˆ’4)(-\infty, -4) satisfies the inequality.
  • For the interval (βˆ’4,5)(-4, 5), let's choose a test value x=0x=0. Substituting x=0x=0 into the quadratic expression, we get (0)2βˆ’(0)βˆ’20=βˆ’20(0)^2-(0)-20=-20. Since βˆ’20<0-20<0, the interval (βˆ’4,5)(-4, 5) does not satisfy the inequality.
  • For the interval (5,∞)(5, \infty), let's choose a test value x=6x=6. Substituting x=6x=6 into the quadratic expression, we get (6)2βˆ’(6)βˆ’20=36βˆ’6βˆ’20=10(6)^2-(6)-20=36-6-20=10. Since 10>010>0, the interval (5,∞)(5, \infty) satisfies the inequality.

Conclusion

Based on the analysis, we can conclude that the intervals (βˆ’βˆž,βˆ’4)(-\infty, -4) and (5,∞)(5, \infty) satisfy the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6. Therefore, a reasonable solution to the inequality is x∈(βˆ’βˆž,βˆ’4)βˆͺ(5,∞)x \in (-\infty, -4) \cup (5, \infty).

Final Answer

The final answer is: (βˆ’βˆž,βˆ’4)βˆͺ(5,∞)\boxed{(-\infty, -4) \cup (5, \infty)}

Introduction

When solving inequalities, it's essential to understand the relationship between the solutions of the corresponding equation and the inequality. In this article, we will explore how to find a reasonable solution to the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6, given that the solutions to the equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6 are x=5x=5 and x=βˆ’4x=-4.

Understanding the Relationship Between Equations and Inequalities

To solve the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6, we need to understand the relationship between the solutions of the corresponding equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6 and the inequality. The equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6 has two solutions, x=5x=5 and x=βˆ’4x=-4. These solutions are the points where the graph of the equation intersects the x-axis.

Graphing the Equation

To visualize the relationship between the equation and the inequality, let's graph the equation x2βˆ’xβˆ’26=βˆ’6x^2-x-26=-6. We can rewrite the equation as x2βˆ’xβˆ’20=0x^2-x-20=0. This is a quadratic equation that can be factored as (xβˆ’5)(x+4)=0(x-5)(x+4)=0. The graph of the equation is a parabola that intersects the x-axis at x=5x=5 and x=βˆ’4x=-4.

Understanding the Inequality

The inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6 is a quadratic inequality that can be rewritten as x2βˆ’xβˆ’20>0x^2-x-20 > 0. This inequality is true for values of xx that make the quadratic expression positive. To find the values of xx that satisfy the inequality, we need to find the intervals where the quadratic expression is positive.

Finding the Intervals

To find the intervals where the quadratic expression x2βˆ’xβˆ’20x^2-x-20 is positive, we need to find the roots of the equation x2βˆ’xβˆ’20=0x^2-x-20=0. The roots of the equation are x=5x=5 and x=βˆ’4x=-4. These roots divide the number line into three intervals: (βˆ’βˆž,βˆ’4)(-\infty, -4), (βˆ’4,5)(-4, 5), and (5,∞)(5, \infty).

Testing the Intervals

To determine which intervals satisfy the inequality x2βˆ’xβˆ’20>0x^2-x-20 > 0, we need to test each interval by substituting a test value into the quadratic expression. Let's test each interval:

  • For the interval (βˆ’βˆž,βˆ’4)(-\infty, -4), let's choose a test value x=βˆ’5x=-5. Substituting x=βˆ’5x=-5 into the quadratic expression, we get (βˆ’5)2βˆ’(βˆ’5)βˆ’20=25+5βˆ’20=10(-5)^2-(-5)-20=25+5-20=10. Since 10>010>0, the interval (βˆ’βˆž,βˆ’4)(-\infty, -4) satisfies the inequality.
  • For the interval (βˆ’4,5)(-4, 5), let's choose a test value x=0x=0. Substituting x=0x=0 into the quadratic expression, we get (0)2βˆ’(0)βˆ’20=βˆ’20(0)^2-(0)-20=-20. Since βˆ’20<0-20<0, the interval (βˆ’4,5)(-4, 5) does not satisfy the inequality.
  • For the interval (5,∞)(5, \infty), let's choose a test value x=6x=6. Substituting x=6x=6 into the quadratic expression, we get (6)2βˆ’(6)βˆ’20=36βˆ’6βˆ’20=10(6)^2-(6)-20=36-6-20=10. Since 10>010>0, the interval (5,∞)(5, \infty) satisfies the inequality.

Conclusion

Based on the analysis, we can conclude that the intervals (βˆ’βˆž,βˆ’4)(-\infty, -4) and (5,∞)(5, \infty) satisfy the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6. Therefore, a reasonable solution to the inequality is x∈(βˆ’βˆž,βˆ’4)βˆͺ(5,∞)x \in (-\infty, -4) \cup (5, \infty).

Q&A

Q: What is the relationship between the solutions of the equation and the inequality?

A: The solutions of the equation are the points where the graph of the equation intersects the x-axis. The inequality is true for values of xx that make the quadratic expression positive.

Q: How do we find the intervals where the quadratic expression is positive?

A: We need to find the roots of the equation x2βˆ’xβˆ’20=0x^2-x-20=0. The roots of the equation are x=5x=5 and x=βˆ’4x=-4. These roots divide the number line into three intervals: (βˆ’βˆž,βˆ’4)(-\infty, -4), (βˆ’4,5)(-4, 5), and (5,∞)(5, \infty).

Q: How do we test each interval to determine which intervals satisfy the inequality?

A: We need to substitute a test value into the quadratic expression for each interval. If the result is positive, the interval satisfies the inequality.

Q: What are the intervals that satisfy the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6?

A: The intervals (βˆ’βˆž,βˆ’4)(-\infty, -4) and (5,∞)(5, \infty) satisfy the inequality.

Q: What is a reasonable solution to the inequality x2βˆ’xβˆ’26>βˆ’6x^2-x-26 > -6?

A: A reasonable solution to the inequality is x∈(βˆ’βˆž,βˆ’4)βˆͺ(5,∞)x \in (-\infty, -4) \cup (5, \infty).

Final Answer

The final answer is: (βˆ’βˆž,βˆ’4)βˆͺ(5,∞)\boxed{(-\infty, -4) \cup (5, \infty)}