can you help me solve?

mr fantastic

MHF Hall of Fame
Dec 2007
16,948
6,768
Zeitgeist
z= -4+5i
Z^3+Az^2+17z-123=0
find the value of A
Substitute z = -4 + 5i into the left hand side. Expand, simplify and equate the real and imaginary parts to zero. Solve for A.