hasil dari xkuadrat -2x -15/xkuadrat -16 : x+3/x+4 adalah...

{(x²-2x-15)/(x²-16)} : {(x+3)/(x+4)}
= {(x-5)(x+3) / (x-4)(x+4)} × {(x+4)/(x+3)}
= {(x-5)(x+3)(x+4)} / {(x-4)(x+4)(x+3)}
= (x - 5) / (x - 4)