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The distance between P(x, 7) and Q(6, 19) is 13 units. Fi...

The distance between P(x, 7) and Q(6, 19) is 13 units. Find the values of x.

A.

1 or -7

B.

1 or 7

C.

1 or 11

D.

5 or -5

Correct answer is C

\(d = \sqrt{(x_{1} - x_{2})^{2} + (y_{1} - y_{2})^{2}}\)

\(13 = \sqrt{(x - 6)^{2} + (7 - 19)^{2}}\)

\(13^{2} = x^{2} - 12x + 36 + 144\)

\(169 = x^{2} - 12x + 180\)

\(x^{2} - 12x + 180 - 169 = 0 \implies x^{2} - 12x + 11 = 0\)

\((x - 1)(x - 11) = 0 \implies x = \text{1 or 11}\)