Answer:

Step-by-step explanation:
<u>Quadratic Formula:</u> 
<u>Quadratic Equation:</u> ax² + bx + x = 0, where a ≠ 0
<u>Given equation:</u> x² + 6x + 9 = 20
<u>Step 1:</u> Subtract 20 from both sides.
x² + 6x + 9 - 20 = 20 - 20
⇒ x² + 6x - 11 = 0
<u>Step 2:</u> Identify the values of <em>a</em>, <em>b</em>, and <em>c</em> and substitute them in the formula.
⇒ a = 1, b = 6, c = -11

<u>Step 3:</u> Separate into possible cases.

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