Question

Which of the following is a solution of x2 − 10x = –36? negative 5 minus i square root of 10 5 plus i square root of 61 negative 5 minus i square root of 11 5 plus i square root of 11

Answer 1

X^2 - 10x + 36 = 0;
We use the quadratic formula: x = ( - b + or - i$\sqrt{ -b^{2}+4ac }$)/ (2a);
We have a = 1; b = -10; c = 36;
Then, x = ( 10 + or -i$\sqrt{44}$)/2 = 5 + or - $\sqrt{11}$)/2 ;