0.925x^2 - 4x + 20 = -1.125x^2 + 6x + 40 (at break even point)
2.05x^2 - 10x - 20 = 0
x = [ - (-10) +/- sqrt(100 - 4*2.05*-20) / (2*2.05)
x = 6.40, -1.52 Ignore the negative
Answer is 6.40
Answer: A
Step-by-step explanation:
1. Swap x and y.
2. Solve for the new y.
Add 8
Divide by 2.
Extract the square root.
Answer:
v = 80 mph
Step-by-step explanation:
Given that,
The distance from Wakefield to London is 180 miles.
The train travels this distance in 2 hours 15 minutes.
We need to find the average speed of the train. The average speed of the train is equal to the total distance covered divided by the time taken.
So, the required average speed of the train is 80 mph.
Answer:
1) decay
2) growth
3) growth
Step-by-step explanation:
A generic exponential function can be written as:
f(x) = A*(r)^x
Where:
A is the initial amount of something.
r is the rate of growth.
x is the variable, usually, represents time.
if r > 1, we have an exponential growth.
if r < 1, we have an exponential decay.
1) f(x) = (3/4)^x
in this case we have:
A = 1
r = (3/4) = 0.75
Clearly, r < 1.
Then this is an exponential decay.
2) f(x) = (1/6)*4^x
In this case we have:
A = (1/6)
r = 4
Here we have r > 1.
Then this is an exponential growth.
3) f(x) = (1/4)*(5/2)^x
in this case we have:
A = 1/4
r = 5/2 = 2.5
here we have r > 1, then this is an exponential growth.
