Question 1127460
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If f(x) = x^2 − 4x − 17and f(c) = 4,find c. 
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{{{c^2-4c-17=4}}}

{{{c^2-4c-17-4=0}}}

{{{c^2-4c-21=0}}}

{{{(c-7)(c+3)=0}}}



c may be  -3, or  +7.