Rationalize the denominator of square root of negative 9 over open parentheses 4 minus 7 i close parentheses minus open parentheses 6 minus 6 i close parentheses.
first we combine the parenthesis to get 9/(-2-i) then we multiply both the numerator and the denomenator by the conjugate of -2-i (whic is -2+i) to get (-18+9i)/5