Answer:
6/5=x/15
Step-by-step explanation:
6/5=x/15,where x is hight of the lamp post
x=18
Answer:
19683
Step-by-step explanation:
As the formula of the geometric sequence:

In the sequence of 1, 3, 9..., you have a1 = 1 and r = 3. Therefore:

Hope this helps!
Answer:
4. dy/dx = -2
8. dy/dx = 1/2 x^(-3/2)
10/ dy/dr = 4 pi r^2
Step-by-step explanation:
4. y = -2x+7
dy/dx = -2(1)
dy/dx = -2
8. y = 4 - x^-1/2
dy/dx = - (-1/2x^ (-1/2-1)
dy/dx = 1/2 x^(-3/2)
10. y = 4/3 pi r^3
dy/dr = 4/3 pi (3r^2)
dy/dr = 4 pi r^2