The answer is 8.2 bc anything above a 5 goes up.
8.16 <<< a 6 is greater than 5. So the 1 goes up to a 2.
Answer:
the rate of change of the water depth when the water depth is 10 ft is; 
Step-by-step explanation:
Given that:
the inverted conical water tank with a height of 20 ft and a radius of 8 ft is drained through a hole in the vertex (bottom) at a rate of 4 ft^3/sec.
We are meant to find the rate of change of the water depth when the water depth is 10 ft.
The diagrammatic expression below clearly interprets the question.
From the image below, assuming h = the depth of the tank at a time t and r = radius of the cone shaped at a time t
Then the similar triangles ΔOCD and ΔOAB is as follows:
( similar triangle property)


h = 2.5r

The volume of the water in the tank is represented by the equation:



The rate of change of the water depth is :

Since the water is drained through a hole in the vertex (bottom) at a rate of 4 ft^3/sec
Then,

Therefore,

the rate of change of the water at depth h = 10 ft is:




Thus, the rate of change of the water depth when the water depth is 10 ft is; 
Answer:
3x+6.9 and 3x-4
Step-by-step explanation:
since 3 x x is 3x and the sign in the bracket is addition you place it there then place 3 x 2.3
being 6.9.
1/3 x 9is 9/3 and 3 can multiply both sides to get 3/1 or 3 then bring the minus and 1/3 x 12 is 12/3 3 can multiply both sides to get 4/1 or 4
Hi there!
So, our two equations are:
2x + 3y = 20 and
-2x + y = 4
We can see that the x's will cancel out because they're the same number, opposite signs. Then we're left with 4y = 24.
Divide 24 by 4, which is 6.
y = 6, then we plug that in to the first equation for y:
2x + 3(6) = 20
2x + 18 = 20
2x = 2
x = 1
So, she made her first mistake when adding the equations, adding 20 and 4, she somehow got 16.
The solution to the system is (1,6).
I hope I helped!