To solve the quadratic equation \(x^2 - 22x + 1 = 15\) by completing the square, we can follow these steps:
-
Start by rearranging the equation: \[ x^2 - 22x + 1 - 15 = 0 \] This simplifies to: \[ x^2 - 22x - 14 = 0 \]
-
Move \(-14\) to the other side: \[ x^2 - 22x = 14 \]
-
To complete the square, take half of the coefficient of \(x\) (which is \(-22\)), square it, and add it to both sides. Half of \(-22\) is \(-11\), and squaring it gives \(121\): \[ x^2 - 22x + 121 = 14 + 121 \] This simplifies to: \[ (x - 11)^2 = 135 \]
-
Now take the square root of both sides: \[ x - 11 = \pm \sqrt{135} \]
-
Finally, solve for \(x\): \[ x = 11 \pm \sqrt{135} \]
Since \(\sqrt{135} = \sqrt{9 \times 15} = 3\sqrt{15}\), the solutions can be expressed as: \[ x = 11 + 3\sqrt{15}, \quad x = 11 - 3\sqrt{15} \]
Thus, the correct response is: \[ x = 11 + 3\sqrt{15}, , 11 - 3\sqrt{15} \]
So the answer is: x=11+315−−√, 11−315−−√.