Answer:
The second one :) Hope it helps
Step-by-step explanation:
1. The correct answer should be A
2. The answer should be C
3. I think the answer is D
4. The answer should be D
Hope this helps :)
Answer: y=2x+1
Step-by-step explanation:
The slope of the line is 
Using the point (1,3) to substitute into point-slope form,

Step-by-step explanation:
We have,
If a quadratic equation with real coefficients has a discriminant of -36.
The general form of quadratic equation is :

The discriminant of this equation is : 
If D=0, it will have 1 real roots
If D>0, it will have 2 real roots
If D<0, it will have no real roots
We have,
D = -36 < 0, so, the quadratic equation will have no real roots.
Answer: A. 
B. A'(5) = 1.76 cm/s
Step-by-step explanation: <u>Rate</u> <u>of</u> <u>change</u> measures the slope of a curve at a certain instant, therefore, rate is the derivative.
A. Area of a circle is given by

So to find the rate of the area:


Using 

Then
![\frac{dA}{dt}=2.\pi.r.[\frac{726}{(t+11)^{3}}]](https://tex.z-dn.net/?f=%5Cfrac%7BdA%7D%7Bdt%7D%3D2.%5Cpi.r.%5B%5Cfrac%7B726%7D%7B%28t%2B11%29%5E%7B3%7D%7D%5D)
![\frac{dA}{dt}=2.\pi.[3-\frac{363}{(t+11)^{2}}].\frac{726}{(t+11)^{3}}](https://tex.z-dn.net/?f=%5Cfrac%7BdA%7D%7Bdt%7D%3D2.%5Cpi.%5B3-%5Cfrac%7B363%7D%7B%28t%2B11%29%5E%7B2%7D%7D%5D.%5Cfrac%7B726%7D%7B%28t%2B11%29%5E%7B3%7D%7D)
Multipying and simplifying:

The rate at which the area is increasing is given by expression
.
B. At t = 5, rate is:




At 5 seconds, the area is expanded at a rate of 1.76 cm/s.