Answer:
x = 2 + sqrt(5) or x = 2 - sqrt(5)
Step-by-step explanation using the quadratic formula:
Solve for x over the real numbers:
7 (x^2 - 4 x - 1) = 0
Divide both sides by 7:
x^2 - 4 x - 1 = 0
Add 1 to both sides:
x^2 - 4 x = 1
Add 4 to both sides:
x^2 - 4 x + 4 = 5
Write the left hand side as a square:
(x - 2)^2 = 5
Take the square root of both sides:
x - 2 = sqrt(5) or x - 2 = -sqrt(5)
Add 2 to both sides:
x = 2 + sqrt(5) or x - 2 = -sqrt(5)
Add 2 to both sides:
Answer: x = 2 + sqrt(5) or x = 2 - sqrt(5)
Answer:
10/20
Step-by-step explanation:
10 times 20 is 200 which would give you 10/20
hope I did this right
(9/18)(9/18) = 81/324. The probability that Amy takes out pink chips in both draws is 81/324.
In this example we will use the probability property P(A∩B), which means given two independent events A and B, their joint probability P(A∩B) can be expressed as the product of the individual probabilities P(A∩B) = P(A)P(B).
The total number of chips of different colors in Amy's bag is:
8 blue chips + 9 pink chips + 1 white chip = 18 color chips
Amy takes out a chip from the bag randomly without looking, she replaces the chip and then takes out another chip from the bag.
So, the probability that Amy takes out a pink chip in the first draw is:
P(A) = 9/18 The probability of takes out a pink chip is 9/18 because there are 9 pink chips in the total of 18 color chips.
Then, Amy replaces the chip an takes out another which means there are again 18 color chips divide into 8 blue chips, 9 pink chips, and 1 white chip. So, the probability of takes out a pink chip in the second draw is:
P(B) = 9/18 The probability of takes out a pink chip is 9/18 because there are 9 pink chips in the total of 18 color chips.
What is the probability that Amy takes out a pink chip in both draws?
P(A∩B) = P(A)P(B)
P(A∩B) = (9/18)(9/18) = 81/324
