When granular materials fall, they form conical piles. The angle of slope, measured from the horizontal, at which the material comes to rest is called
the angle of repose. The angle of repose is related to the height h and base
r radius r of the conical pile by the equation 0 = cot-1 r/h. When a certain granular material is stored in a pile 8 feet high, the diameter of the base of the pile is 65 feet. What is the base diameter of a pile that is 17 feet high?

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -

the furthest the dog can be is 508 meters away from the house, and the closest he can be is 492 meters away from the house.