Question

a rectangular plot of land has a perimeter of 40m. if the area of the plot is at least 75 m, what is the narrowest that this plot of land can be?

Answer 1

what is the widest?

Answer 2

i got (x-15)(x-5)>=0

is this correct?
what is the answer?

Answer 3

@eta

Answer 4

See:
you are given perimeter :
\[2l + 2w = 40 \\ l + w = 20\]

Answer 5

i got xy>=75 and 2x+2y=40 as my 2 equations

Answer 6

i was taught to solve for 2x+2y=40 and then plug it into the inequality

Answer 7

yes these two equations are right..

Answer 8

then i got (x-15)(x-5)>=0

Answer 9

yes, do the same..

Answer 10

but what is the answer?

Answer 11

i found that its (inf,5] and [15,inf)

Answer 12

How you got that?

Answer 13

I mean : \(x + y = 20\), right?

Answer 14

So, \(y = 20 - x\)

Answer 15

yea