<span>Critical points are where the derivative is 0, i.e. where it crosses the x - axis
The Critical points lies where the derivative is 0, while it crosses the x-axis, SO, in this case the choice 3 looks like best answer for this.
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Answer:
The time t is the independent variable while the volume V is the dependent variable
Step-by-step explanation:
A variable is a parameter that changes.
We have two types namely dependent and independent variables.
A dependent variable is a variable which its value needs to be determined based on the value of another variable while and independent variable is a variable which its value independent of other parameters.
In our question, It takes 1 hour (t) to fill the water tank of volume (V) 750 m3.
The volume of the tank V changes as time changes. So the volume of the tank V is dependent on time, t.
So V is proportional to t
Since the volume of the tank is the variable that needs to be determined based on another variable-which is time,t- it is the dependent variable, while the time,t is the independent variable since its value is not determined based on other parameters.
Let;
A(-8,6) B(6,6) C(6, -4) D(-8, -4)
Let's find the length AB
x₁= -8 y₁=6 x₂=6 y₂=6
We will use the distance formula;
![d=\sqrt[]{(x_2-x_1)^2+(y_2-y_1)^2}](https://tex.z-dn.net/?f=d%3D%5Csqrt%5B%5D%7B%28x_2-x_1%29%5E2%2B%28y_2-y_1%29%5E2%7D)
![=\sqrt[]{(6+8)^2+(6-6)^2}](https://tex.z-dn.net/?f=%3D%5Csqrt%5B%5D%7B%286%2B8%29%5E2%2B%286-6%29%5E2%7D)
![=\sqrt[]{14^2+0}](https://tex.z-dn.net/?f=%3D%5Csqrt%5B%5D%7B14%5E2%2B0%7D)
Next, we will find the width BC
B(6,6) C(6, -4)
x₁= 6 y₁=6 x₂=6 y₂=-4
substitute into the distance formula;
![d=\sqrt[]{(6-6)^2+(-4-6)^2}](https://tex.z-dn.net/?f=d%3D%5Csqrt%5B%5D%7B%286-6%29%5E2%2B%28-4-6%29%5E2%7D)
![=\sqrt[]{(-10)^2}](https://tex.z-dn.net/?f=%3D%5Csqrt%5B%5D%7B%28-10%29%5E2%7D)
![=\sqrt[]{100}](https://tex.z-dn.net/?f=%3D%5Csqrt%5B%5D%7B100%7D)
Area = l x w
= 14 x 10
= 140 square units
