Show how to subtract partial products to divide 876 by 3

What is the missing reason in step 5? linear pair postulategivendefinition of complementary anglescongruent complements theorem

Astuntman jumping off a 20-m-high building is modeled by the equation h=20-5t^2, where t is the same in seconds. a high-speed camera is ready to film him between 15m and 10m above the ground. for which interval of time should the camera film him?

X+ y = 5 ; x - y =3 solve using linear combination