Respuesta :
-1 2
------------- - -----------------
x - 9 x + 7
-1(x+7) - 2(x-9)
= --------------------------
(x - 9)(x+7)
-x - 7 - 2x + 18
= --------------------------
(x - 9)(x+7)
-3x + 11
= ------------------
(x - 9)(x+7)
Answer is D. Last choice
------------- - -----------------
x - 9 x + 7
-1(x+7) - 2(x-9)
= --------------------------
(x - 9)(x+7)
-x - 7 - 2x + 18
= --------------------------
(x - 9)(x+7)
-3x + 11
= ------------------
(x - 9)(x+7)
Answer is D. Last choice