Question

Solve by completing the square.

x² + 10x = -81
O {6+i√42, 6-i√/42}
O {12+√133, 12-√133}
O {11, 1}
O {-5+2i√/14, -5-2i√/14}

Answer 1

Option 4

Explanation:

`x^2+10x=-81 \\ \\ x^2+10x+25=-56 \\ \\ (x+5)^2=-56 \\ \\ x+5= \pm √(-56)=\pm 2i √(14) \\ \\ x=-5 \pm 2i √(14)`