Answer: 
Step-by-step explanation:
GCF = Greatest common factor.
For example: 6 is the GCF of 12 and 18.
The given expression: 
It can be written as

Taking out common factor
, we get
![5y(x^2-6xy-7y^2)\\\\ =5y(x^2+xy-7xy-7y^2)\ \ [\because-6xy=xy-7xy]\\\\=5y(x(x+y)-7y(x+y))\\\\= 5y((x+y)(x-7y))\\\\=5y(x+y)(x-7y)](https://tex.z-dn.net/?f=5y%28x%5E2-6xy-7y%5E2%29%5C%5C%5C%5C%20%3D5y%28x%5E2%2Bxy-7xy-7y%5E2%29%5C%20%20%5C%20%5B%5Cbecause-6xy%3Dxy-7xy%5D%5C%5C%5C%5C%3D5y%28x%28x%2By%29-7y%28x%2By%29%29%5C%5C%5C%5C%3D%205y%28%28x%2By%29%28x-7y%29%29%5C%5C%5C%5C%3D5y%28x%2By%29%28x-7y%29)
Hence, 
Answer:
The probability that the sample mean will lie within 2 values of μ is 0.9544.
Step-by-step explanation:
Here
- the sample size is given as 100
- the standard deviation is 10
The probability that the sample mean lies with 2 of the value of μ is given as

Here converting the values in z form gives

Substituting values

From z table

So the probability that the sample mean will lie within 2 values of μ is 0.9544.
Answer:

Step-by-step explanation:
<u>Exponential Growth
</u>
The natural growth of some magnitudes can be modeled by the equation:

Where P is the actual amount of the magnitude, Po is its initial amount, r is the growth rate and t is the time.
The initial number of bacteria is Po=40 and it doubles (P=2Po) at t=20 min. With that point we can find the value of r:

Simplifying:

Solving for 1+r:
![1+r=\sqrt[20]{2}](https://tex.z-dn.net/?f=1%2Br%3D%5Csqrt%5B20%5D%7B2%7D)

The exponential function that models the situation is:

Answer:
OK so the equation has a exponent so if there is a exponent then you need to multiply. since 227 is the Area and the exponent is 2.
Step-by-step explanation:
Answer:
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Step-by-step explanation: