zz3+zz3=350 ⇒zz(z2+z2)=350 Let z=x+iy ⇒z=x−iy ∴(x+iy)(x−iy)[(x+iy)2+(x−iy)2]=350 ⇒(x2+y2)⋅2(x2−y2)=350 ⇒(x2+y2)(x2−y2)=175=25×7 ⇒x2+y2=25 and x2−y2=7 On adding Eqs. (i) and (ii), 2x2=32 ⇒x2=16⇒x=±4 and y2=9⇒y=±3 ∴ Vertices of the rectangle are (4,3),(4,−3),(−4,−3) and (−4,3)