i dont understand this question i am confused
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Answer:
y=x²-8x+17.
Step-by-step explanation:
1) no roots is if Δ=(b/2)²-ac<0 (y=ax²+bx+c);
2) according to the rule above y=x²-8x+17 is correct answer only, for 16-17<0.
P.S. for more info see the attached graph.