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If (y = x^{2} – 6x + 11) is written in the form (y =…

If (y = x^{2} – 6x + 11) is written in the form (y = a(x – h)^{2} + k), find the value of ((a + h + k)).

  • A.
    -4
  • B.
    -3
  • C.
    0
  • D.
    6
Correct Answer: Option D
Explanation

(y = x^{2} – 6x + 11)

( y = a(x – h)^{2} + k)

(a(x – h)^{2} + k = a(x^{2} – 2hx + h^{2}) + k)

(ax^{2} – 2ahx + ah^{2} + k = x^{2} – 6x + 11)

Comparing, we have

(a = 1)

(2ah = 6 implies 2h = 6; h = 3)

(ah^{2} + k = 11 implies (1 times 3^{2}) + k = 11)

(9 + k = 11 implies k = 2)

(therefore a + h + k = 1 + 3 + 2 = 6)