Question

How do you solve using the quadratic formula: `x^2+x+4=0`?

Answer 1

Solution is `(-1+isqrt15)/2` and `(-1-isqrt15)/2`

Explanation:

For an equation `ax^2+bx+c=0`, quadratic formula gives the solution as `(-b+-sqrt(b^2-4ac))/(2a)`.

As in the given equation `x^2+x+4=0`, `a=1, b=1` and `c=4`

Solution is given by `(-1+-sqrt(1^2-4*1.4))/(2*1)` or

`(-1+-sqrt(-15))/2` or `(-1+-isqrt15)/2`

Hence solution is `(-1+isqrt15)/2` and `(-1-isqrt15)/2`