Answer:
Answer is x = 4 (or) x = -2
Step-by-step explanation:
[tex]given \: \: f(x) = x {}^{2} - 2x + 3 \\ and \: f(x) = 11 \\ substituting \: the \: values \\ 11 = x {}^{2} - 2x + 3 \\ x {}^{2} - 2x - 8 = 0 \\ by \: factorization \\ (x - 4)(x + 2) = 0 \\ x = 4 \: \:( or) \: x = - 2[/tex]
Value of x is 4 or -2.
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