Answer:
x = 4
y = -3
Step-by-step explanation:
We can use substitution, elimination, or graphically.
Step 1: Rearrange first equation
2x + 4y = -4
2x = -4 - 4y
x = -2 - 2y
Step 2: Rewrite systems of equations
x = -2 - 2y
3x + 5y = -3
Step 3: Substitution
3(-2 - 2y) + 5y = -3
-6 - 6y + 5y = -3
-6 - y = -3
-y = 3
y = -3
Step 4: Find <em>x</em> using <em>y</em>
2x + 4(-3) = -4
2x - 12 = -4
2x = 8
x = 4
Graphically:
Use a graphing calc and analyze where the 2 lines intersect.
Since the operation between the two sets of parentheses is addition, we don't have to do anything with it, and can remove the parentheses.
Our new expression is: 2y^2+9y+4-3y^2-3y-9
Now, we just add like terms together to solve for the simplest form of the expression.
2y^2+9y+4-3y^2-3y-9
(2-3)y^2+(9-3)y+(4-9)
-y^2+6y-5
Our final answer is -y^2+6y-5.
Answer:15
Step-by-step explanation:
Apex
Answer:
P(X=3) = 0.2013
Step-by-step explanation:
After taking and tagging the first 20 birds, then we have a proportion of 20% of tagged birds within the population, that is


Supposing that the probability (0.20) of capturing a bird <em>remains constant</em>, we may resolve it as it follows:
Capturing 10 birds can be considered as a binomial experiment with a success probability p = 0.2
Let,
be the expression of the binomial distribution, for our case we have:
p=0.2
x = 3
n=10
Then,


Therefore, the probability that exactly 3 of the 10 birds in the new sample were previously tagged is 20.13%