Answer :
Answer:
-90=[tex]x[/tex]([tex]x[/tex]-18)
-90=[tex]x^{2}[/tex]-18[tex]x[/tex]
[tex]0=x^{2}-18x+90[/tex]
[tex]x=9+3i or 9-3i[/tex]
Step-by-step explanation:
you need to use quadratic formula and you will find square root a negative ( -9 ), which is an imaginary no.
square root (-9) = 3i