Answer:
3/a-5
Step-by-step explanation:
first of all you have to open the equatıon:
a2+8a+15= (a+3).(a+5)
a2+7a+12= (a+3).(a+4)
3a+12=3(a+4)
a2-25=(a-5).(a+5)
now ın this equation you can delete the same brackets:
(a+3).(a+5)÷(a+3).(a+4)= (a+5)÷(a+4)
3(a+4)÷(a-5)(a+5).(a+5)÷(a+4)= 3(÷a-5)
