Question

Find the perimeter of the following shape, rounded to the nearest tenth:


(pic in replies)


12.5
15.7
16
16.5

Answer 1

Do you know the distance formula?

Answer 2

no...

Answer 3

Have you seen this formula before?

\( \text{distance} = \sqrt{(x_2 - x_1)^2 + (y_2-y_1)^2} \)

Answer 4

nope/

Answer 5

mhmm have you learned about special triangles then perhaps?

Such as the 45-45-90 degree triangle

Or Pythagoras theorem?
a^2 + b^2 = c^2

Answer 6

I know all sides angles equal 180 0-0

Answer 7

thas bout it

Answer 8

To find the perimeter, we have to find the lengths of each side and then add them up

Answer 9

What are the coordinates of point A?

Answer 10

(5,5)

Answer 11

Good! What about point B?

Answer 12

(7,3)?

Answer 13

Perfect!

Now to find the length of that side that's between point A and B, we use the distance formula

\( d = \sqrt{(x_2 - x_1)^2 + (y_2-y_1)^2}\)

where you have two points \( (x_1, y_1)\) and \( (x_2, y_2)\)

Answer 14

@AZ

Answer 15

So we have the two points you mentioned

(5, 5) and (7, 3)

it's in the form of

\( (x_1, y_1)\) and \( (x_2, y_2)\)

So let's plug in the numbers and simplify, okay?

Answer 16

it would be 2.83?

Answer 17

well if you simplify

Answer 18

\( d = \sqrt{(7- 5)^2 + (3-5)^2} \)

Answer 19

Good! That's one of the sides of our rectangle.

Answer 20

What are the points C and D?

Answer 21

another side would be 5

Answer 22

Yes!!! You can also see that if you drew a triangle with that side as the hypotenuse, that it would form a 3, 4, 5 triangle

Answer 23

so then you add those and multiply by 2 because its a rectangle right?

Answer 24

So now we have

Answer 25

Yes! Exactly!

Answer 26

15.66??

Answer 27

theres only 15.7 on there. So I think im supposed to round

Answer 28

That's your answer!

Answer 29

\(\color{#0cbb34}{\text{Originally Posted by}}\) @AZ
That's your answer!
\(\color{#0cbb34}{\text{End of Quote}}\)
thank you!!!

Answer 30

It was my pleasure! :)