Pam is playing with red and black rocks. The number of red rocks she has is three more than twice the number of black rocks she
1 answer:
You might be interested in
Answer:
The population will be 896 turtles 6 years later ⇒ B
Step-by-step explanation:
The exponential increasing formula is y = a, where
- y is the new value
- a is the initial value
- r is the rate of increase in decimal
- x is the time in years
∵ There are 300 turtles
∴ a = 300
∵ The population of the turtles exponentially increases 20% each year
∴ r = 20%
→ Divide it by 100 to change it to decimal
∵ 20% = 20 ÷ 100 = 0.2
∴ r = 0.2
∵ The time is 6 years
∴ x = 6
→ Substitute these values in the exponential formula above
∵ y = 300
∴ y = 300
∴ y = 895.7952
→ Round it to the nearest whole number
∴ y = 896
∴ The population will be 896 turtles 6 years later
9514 1404 393
Answer:
a) x = (√5 -1)/2 ≈ 0.618034
b) 1/x = (√5 +1)/2 ≈ 1.618034
Step-by-step explanation:
<u>Given</u>:
x/(1 -x) = 1/x
<u>Find</u>:
Exactly, and as a decimal approximation, ...
a) x, using the quadratic formula
b) 1/x
<u>Solution</u>:
a) We can multiply the given equation by x(1 -x) to obtain ...
x² = 1 -x
x² +x -1 = 0 . . . . . . add x-1
The coefficients for use in the quadratic formula are a=1, b=1, c=-1. The solution using the quadratic formula is ...
We are only interested in the positive solution, which is ...
__
b) The quadratic we developed in the first part can be rearranged like this:
x² +x = 1 . . . . . . add 1 to both sides
x(x +1) = 1 . . . . . factor out x
x +1 = 1/x . . . . . .divide by x
Then to find the value of 1/x, we simply need to add 1 to the value of x we have: