Question

Part A: Angelina plans to put a fence along the length AD of her lawn. What is the length of the fence required?
Part B: Using complete sentences, explain how you arrived at the answer for Part A.

Answer 1

there a diagram

Answer 2

use pythagorean theorem to figure out BD first.

Answer 3

Hint:
Pythagorean Theorem and the 30-60-90 theorem http://puu.sh/qsq6
http://www.themathpage.com/atrig/30-60-90-triangle.htm

Answer 4

aww.. to fast for me zepp

Answer 5

Or, law of sines.

Answer 6

what?

Answer 7

website seems more complex than necessary for this question tho zepp

Answer 8

u kno what pythagorean theorem is right.

Answer 9

Alright then, forget the 30-60-90 theorem, can you find the measure for BD?

Answer 10

\[c ^{2}=a ^{2}+b ^{?}\]

Answer 11

last ? was a 2

Answer 12

12 squared + 35 squared= C squared?

Answer 13

yup

Answer 14

1369 is C?

Answer 15

now sqrt that.

Answer 16

2 squared + 35 squared= C^2
1369 = C^2

You forgot a step ;)

Answer 17

yup

Answer 18

1,874,161

Answer 19

That's 1369 squared
If you want C and you have
1369 = C^2
You have to do
\[\sqrt(1369) = \sqrt(C^2)\]
\[\sqrt(1369) = C\]

Answer 20

37

Answer 21

Alright, now you have the length of BD
Find the red colored angle I drawn on this http://puu.sh/qsx0

Answer 22

30

Answer 23

When you have it, use
\[sinA/A = sinB/B\]

Answer 24

...huh?

Answer 25

Do you know the law of sines?

Answer 26

No I don't think so

Answer 27

Alright, you have to use the 30 - 60 - 90 theorem, look at this http://puu.sh/qsAi
This means that the short leg / long leg 's ratio is 1: sqrt(3), (If the short leg's length is 1, long's leg's length would be sqrt(3)) short leg / hypotenuse is 1:2 etc etc.
In you picture, BD is the length opposing the 60 degree angle, it's the long leg, and what you have to find is AD, which is the short leg
By following the ratio, you have short leg / long leg, ratio is 1: sqrt(3)
\[1 : \sqrt(3) = x : 37\]
\[1/ \sqrt(3) = x/37\]
And solve it, x will be the short leg(AD) 's length, good luck :)

Answer 28

oh my god I don't get it..

Answer 29

Lemme draw something hold on

Answer 30

http://puu.sh/qsI5
Do you understand this ratio?

Answer 31

yes

Answer 32

I got like 0.15

Answer 33

Alright, what we need in this situation is the length of AD, we already know the length of BD, which is 37ft, we will do this: http://puu.sh/qsK0

Answer 34

Oops, sorry, it's this one: http://puu.sh/qsKI

Answer 35

okayy

Answer 36

Basically, what this is saying, is that in a rectangle triangle, if the side facing the 60 degree angle is the long leg, if the short leg = 1, the long leg would be = sqrt(3), and based on this, you'll find the solution to your problem

Answer 37

okay! Thanks!

Answer 38

So you'll get
\[\frac{1}{\sqrt{3}} = \frac{x}{37}\]
x = 21.36
You're welcome :)