1. **State the problem:** Solve the quadratic equation $x^2 + 20x + 82 = 7$ by completing the square.
2. **Rewrite the equation:** Move the constant term on the left side to the right side:
$$x^2 + 20x = 7 - 82$$
$$x^2 + 20x = -75$$
3. **Complete the square:** Take half of the coefficient of $x$, which is 20, divide by 2 to get 10, then square it to get $10^2 = 100$.
4. **Add 100 to both sides to complete the square:**
$$x^2 + 20x + \cancel{100} = -75 + \cancel{100}$$
$$x^2 + 20x + 100 = 25$$
5. **Rewrite the left side as a perfect square:**
$$(x + 10)^2 = 25$$
6. **Take the square root of both sides:**
$$x + 10 = \pm \sqrt{25}$$
$$x + 10 = \pm 5$$
7. **Solve for $x$:**
- For the positive root:
$$x + 10 = 5$$
$$x = 5 - 10 = -5$$
- For the negative root:
$$x + 10 = -5$$
$$x = -5 - 10 = -15$$
8. **Order the solutions from least to greatest:**
$$x = -15, -5$$
Completing Square 93E02A
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