(x-7)^2=81

2 min read Jun 17, 2024
(x-7)^2=81

Solving the Equation (x-7)^2 = 81

This article will walk through the process of solving the equation (x-7)^2 = 81. We will explore both algebraic and conceptual approaches to understand the solutions.

Understanding the Equation

The equation represents a quadratic equation, where the left side is a perfect square trinomial. This means the expression can be factored into the form (x - a)^2, where 'a' is a constant.

Solving by Square Root Property

  1. Isolate the squared term: The equation is already in this form.

  2. Take the square root of both sides: Remember to include both positive and negative roots.

    √(x-7)^2 = ±√81

  3. Simplify:

    x - 7 = ±9

  4. Solve for x:

    x = 7 ± 9

  5. Find the two solutions:

    • x = 7 + 9 = 16
    • x = 7 - 9 = -2

Therefore, the solutions to the equation (x-7)^2 = 81 are x = 16 and x = -2.

Visualizing the Solution

The equation can also be interpreted geometrically. The equation represents a parabola that is shifted 7 units to the right and opens upwards. The solutions to the equation are the x-coordinates where the parabola intersects the line y = 9 and y = -9.

Conclusion

By using the square root property, we effectively solved the quadratic equation (x-7)^2 = 81 and found two distinct solutions: x = 16 and x = -2. Understanding the process and the visual interpretation helps us gain a deeper understanding of quadratic equations and their solutions.