How do you solve #-3x^2-9=0#?

2 Answers
Mar 15, 2018

sqrt3*i

Explanation:

#-3x^2-9=0 rArr -3x^2=9 rArr x^2=9/-3 rArr x^2=-3 rArr x= sqrt(-3) rArr x= sqrt(3*-1) rArr x= sqrt3*i [as sqrt-1=i]#

Mar 15, 2018

#x=isqrt3#

Explanation:

We can start by adding #9# to both sides to get

#-3x^2=9#

Next, we can divide both sides by #-3# to get

#x^2=-3#

We can take the square root of both sides. NOTE: We are taking the square root of a negative number, so we will have a complex solution.

#x=sqrt(-3)#

#=>x=color(blue)(sqrt(-1))*sqrt3#

#=>x=color(blue)isqrt3#

NOTE: #sqrt(-1)=i#

Our final solution is

#x=isqrt3#