r - Quadratic Function with Complex Numbers -

i'm writing function in r needs solve basic quadratic equation , gives roots. need print out imaginary numbers if applicable. below code. give me advice on how improve coding?

quad = function(a, b, c){  d = b^2 - 4*a*c  if (d < 0){    cat("the roots are", x, "and", y,"i\n");    z < - complex(real = x, imaginary = y)    return();  }   x = (-b - d^0.5)/(2*a)  y = (-b + d^0.5)/(2*a)  cat("the 2 roots are", x, "and", y, "\n"); } 

just keep in mind i'm incredibly new r programmer, , aware incredibly simple code. advice appreciated.

you can use simple code.

 quadr=function(a,b,c){    d=b^2-4*a*c    m=ifelse(d<0,complex(1,0,sqrt(abs(k))),sqrt(k))    c((-b+m)/(2*a),(-b-m)/(2*a))   }   quadr(1,1,6)  [1] -0.5+2.397916i -0.5-2.397916i   quadr(1,1,-6)  [1]  2 -3