Question

Find a formula
A rectangle has perimeter 8 m. Express the area A of the rectangle as a function of the length, L, of one of its sides.
I got A(L)=4L-L^2
I need to find the domain
Assume the length of the rectangle is longer than its width. Enter your answer in interval notation

How to find it?

Answer 1

so ur equation is A(L)= 4L-L^2 ?

Answer 2

yes

Answer 3

ok so what u do is

Answer 4

u can always try to graph ur equation first

Answer 5

and L>w
L> 4-L

Answer 6

so u obviously know that this equation is a parabola, a negative one

Answer 7

4L - L^2 > 0
the values which will satisfy this inequality is the domain 'cause area can't be a negative value or zero

Answer 8

yes @music101

Answer 9

ok so when u graph it, it will be like from -inf to pos. infi

Answer 10

but

Answer 11

so u could say that the domain is all real numbers

Answer 12

but since this is a word problem & ur talking abt length/width, I don't think u can have a negative domain????

Answer 13

No Icannot