<span>In the function "y=x2-18x" the goal is to find the value of the letter x. We know that y equals x2-18x. First, recognize that x2 is the same thing as 2x. So changing the problem to "y=2x-18x". We can subtract 18x from 2x, which leaves us with -16x. Now the problem looks like this: y=-16x. In order to get x by itself, we will need to do the same thing to both sides of the equation. In this case, we want the answer to be x by itself, or (1x) which is the same thing. We divide both sides of the equation by (-16). We are left with the following: y/-16=x. Basically, in words, x equals y divided by negative 16.</span>
Answer: 300π
Step-by-step explanation: Volume=(pi)(radius^2)(height)
Volume=(pi)(5^2)(12)
V=(pi)(25)(12)
V=(pi)(300)
-3 • (5x + 2y = 7)
-15x - 6y = -21
-2x + 6y = 9
__________
-17x = -12
x = 12/17
5(12/17) + 2y = 7
2y = 7 - 60/17
2y = 3.47
y = 1.735
87 24/25.......24/25 = 0.96......answer is 87.96
224 7/10....7/10 = 0.7....answer is 224.7
686 49/50...49/50 = 0.98...answer is 686.98
Answer:
The probability is 0.9211
Step-by-step explanation:
Let's call K the event that the student know the answer, G the event that the student guess the answer and C the event that the answer is correct.
So, the probability P(K/C) that a student knows the answer to a question, given that she answered it correctly is:
P(K/C)=P(K∩C)/P(C)
Where P(C) = P(K∩C) + P(G∩C)
Then, the probability P(K∩C) that the student know the answer and it is correct is:
P(K∩C) = 0.7
On the other hand, the probability P(G∩C) that the student guess the answer and it is correct is:
P(G∩C) = 0.3*0.2 = 0.06
Because, 0.3 is the probability that the student guess the answer and 0.2 is the probability that the answer is correct given that the student guess the answer.
Therefore, The probability P(C) that the answer is correct is:
P(C) = 0.7 + 0.06 = 0.76
Finally, P(K/C) is:
P(K/C) = 0.7/0.76 = 0.9211
