Question

Barry had a rectangular farm with dimensions x feet and 20 feet. He put a fence along 30 feet of the boundary of the farm.

An expression is shown below:

(2x + 40) - 30

Part A: What does the expression represent?

Part B: What does 2x + 40 represent?

Part C: What does 2x represent?

Answer 1

What is the perimeter of the farm?

Answer 2

2x + 40

Answer 3

Right?

Answer 4

Right.
Notice that 2x + 40 is part of the expression.
A fence all around the farm is 2x + 40 feet long.
He already put up 30 feet of fencing.
How much fencing does he still need to put up?

Answer 5

2x + 10?

Answer 6

Yes, that is correct, but if you start with 2x + 40, what do you do with 30 to end up with
(2x + 40) - 30?

Answer 7

I'm sorry, I don't know. I want to say you would have to subtract 30 but I don't think that's right.

Answer 8

That's exactly it
(2x + 40) - 30 represents 30 subtracted from 2x + 40.

Since 2x + 40 is the perimeter of the farm, the fence needs to be 2x + 40 feet long.
He already fenced 30 ft, so he has (2x + 40) - 30 ft of fencing left to do.

Answer 9

Cool! And 2x is the width of the rectangular farm?

Answer 10

Careful there. x is the width. 2x is the sum of the two widths.

Answer 11

A. the amount of fencing left to do
B. the perimeter of the farm
C. the sum of the two widths

Answer 12

Thank you very much!! :)

Answer 13

wlcm