Question

I need help adapppppppp

Answer 1

18. D

19. A

20. the y-intercept is 5000 and it represents the initial amount in the savings account

Explanation:

For vertical translation of an exponential function, we can remember the following rules:

If exponential function is given in the form
`f(x)=a^x` where a is a constant, then

1.
`f(x)=a^x + b` is the original shifted b units up, and

2.
`f(x)=a^x -b` is the original shifted b units down

Hence, we can say that to shift the function given in the problem, we will "add a 5" to it.

Thus,
`f(x)=4^x +5` is the correct answer.

19.

THis problem can be solved using the exponential growth equation shown below:

`F=I(1*G)^x`

Where

F is the future amount (4300 in this case)

I is the initial value/amount (325 given)

G is the Growth Factor ("double", "triple" etc. This case it says double so G = 2)

x is the time period

Putting the known values, we can get the equation as:

`F=I(1*G)^x\\4300=325(1*2)^x\\4300=325(2)^x\\4300=325*2^x`

A is the correct answer.

20.

y-intercept is the point when x = 0. Let's put it and see what the value is:

`y=5000(0.98)^x\\y=5000(0.98)^0\\y=5000(1)\\y=5000`

Note: anything to the 0th power is 1

Thus the y-intercept is 5000 and it represents the initial amount in the savings account