What are the solutions of the equation open paren 2 x plus 3 close paren squared plus 8 times open paren 2 x plus 3 close paren plus 11 is equal to 0 ? Use u substitution and the quadratic formula to solve.

Let u = 2x + 3. Then the equation becomes u² + 8u + 11 = 0, whose solutions by the quadratic formula are u = (−8 ± √(64 − 44))/2 = −4 ± √5. Substitute back: 2x + 3 = −4 ± √5, so x = (−7 ± √5)/2. These are the solutions in choice B.

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