Answer:
n²-7n-21
Explanation:
Given the expression:

First, open the brackets:

Next, bring the like terms together and simplify:

Answer:

Step-by-step explanation:
First, let's change those variables to x and y, just for the sake of convenience. In order to find the inverse of a function algebraically, switch the x and y coordinates, then solve for the new y. Letting y = A(n) and x = n (we will switch them back when we're done):
y = 3x - 20. This is linear; a line with a slope of 3 and a y-intercept of -20. When we switch the x and the y, we get:
x = 3y - 20. Now we solve for the new y. Begin by adding 20 to both sides:
x + 20 = 3y. Now divide both sides by 3:
, or to write it in slope-intercept form, like the function you started with:

This is also a line, with a slope of 1/3 and a y-intercept of +20/3
Now, replacing:

That is how to write the inverse using function notation. The little -1 as an exponent tells us that this is the inverse of the function A(n).
Let's the length to be x,
then the width is 8x - 2.
Perimeter of a rectangle = 2*Width + 2*Length
Perimeter of the rectangle = 2(8x-2) + 2x = 16x - 4 + 2x = 18x - 4
Ar the same time, Perimeter of the rectangle = 88.
So, we can write
18x - 4 = 88
18x = 84
9x=42
x= 42/9 cm (length) or ≈ 4.67 cm (length)
8x - 2 = 8*42/9 - 2 ≈ 35.33 cm (width)
Answer:
2.5 years
Step-by-step explanation:
Given data
P=9000
r= 1.25%
A= 9281.25
The simple interest expression is given as
A=P(1+rt)
substitute
9281.25= 9000(1+0.0125*t)
9281.25=9000+112.5t
collect like terms
9281.25-9000=112.5t
281.25= 112.5t
t= 281.25/112.5
t= 2.5
Hence the time is 2.5 years