Question

Can someone help me with this question for a medal?

Answer 1

The following table shows the length and width of two rectangles:


Length Width
Rectangle A 3x + 2 2x - 1
Rectangle B x + 5 5x - 1


Which expression is the result of the perimeter of rectangle B minus the perimeter of rectangle A?

2x + 2
2x + 6
22x + 14
22x + 18

Answer 2

@MikeyMaximum

Answer 3

@january123

Answer 4

@Jaynator495

Answer 5

If a rectangle has length L and width W, what is it's perimeter?

Answer 6

Sorry. I'm not sure how to do this question and I don't know the answer to your question.

Answer 7

The perimeter is the distance around the outside of an object. To find it for an object made of straight lines, we just add up the length of all the sides.

For a rectangle, the perimeter is L+W+L+W = 2(L+W)

Find the perimeter of each of the rectangles.

Answer 8

Okay, give me a minute

Answer 9

Okay, I'm confused by the formula. L+w+L+W=2(L+W) The length for rectangle A is 3x+2 and the width is 2x-1. I don't see that working out

Answer 10

2*((3x+2)+(2x-1)) = 2*(5x+1) = 10x+2

Answer 11

Can you do the other rectangle?

Answer 12

Like I said, I am really confused. I don't see what you did to have gotten that. So, at the moment, I can't.

Answer 13

Alright, I'll break it down a bit more.

We start with:
\[2\times [(3x+2)+(2x-1)]\]
First, we'll deal with what's inside the braces [ ]

3x+2+2x-1
We add the terms that have an x in them:
3x+2x = 5x
Then we add the terms that don't:
2-1 = 1
We're then left with:
\[2\times[5x+1]\]
Finally, we distribute the 2 and get the answer:
10x+2

Answer 14

Okay, so this is for rectangle a. Correct?

Answer 15

Correct. Can you find the perimeter of rectangle B?

Answer 16

I'll see what I can do. Sorry for being a pain.

Answer 17

No worries. We all had to learn this stuff at some point :)

Answer 18

So, I start off with 5x[(x+5)+(5x-1)] ?

Answer 19

2[(x+5)+(5x-1)]

Answer 20

Oh, so will it always be a 2?

Answer 21

For a rectangle, yeah. You have two sides of length L, and two sides of length W

Answer 22

Alright. I figured you got the 2x from the width of rectangle A. Okay, I understand now.

Answer 23

6x+4?

Answer 24

Forgot your 2 out front
2(6x+4)

Answer 25

Oh, sorry forgot to distribute.12x+8?

Answer 26

Yeah, what you said. I'm honestly not sure if thats distribution, but...

Answer 27

yep!

Now we know the perimeter of both rectangles.

Take the perimeter of rectangle B and subtract rectangle A

Answer 28

2x+2?

Answer 29

Not quite.

The perimeter of rectangle A was 10x+2

(12x+8)-(10x+2) = ?

Answer 30

Oh my god. I'm sorry I was looking at 12x+8 and 6x+4 at the same time, and somehow got them both mixed together. Yeah, 2x+6

Answer 31

Wow, made myself look really stupid.

Answer 32

Nah, that stuff happens all the time :)

Good job!

Answer 33

Alright, thank you for taking nearly 40 minutes of your time to help me! For wasting that much of your time, I'll give you a fan as well!

Answer 34

My pleasure. Keep it up!