Question

Use △DEF, shown below, to answer the question that follows:

Triangle DEF where angle E is a right angle. DE measures x. DF measures 55. Angle D measures 49 degrees.

What is the value of x rounded to the nearest hundredth? Type the numeric answer only in the box below.
http://learn.flvs.net/webdav/assessment_images/educator_geometry_v16/0702_g1_q2.gif

Answer 1

please help me i need to pass geometry to graduate thanks <3

Answer 2

can you upload the photo because the link isn't working

Answer 3

here you go

Answer 4

@horsegirl27 let's help her together

Answer 5

First, welcome to OS! Second, what exactly do you need help on? I will help, however I just need to see what part you're confused by then you can learn the material rather than just the answer.

Answer 6

simply put i just need to understand how to find a missing side or angle. the FLVS course explains it but it kind of goes right over my head
if you can give me a step by step on how to solve the problem at the top i would greatly appreciate it

Answer 7

I'll try my best, just bear with me as I may be a little slow at remembering how to do this. I'll try my best to explain the entire process simply

Answer 8

Let's start with finding a missing angle. Then I'll explain finding a missing side.

Answer 9

thats fine i have all night lol
thanks for even trying though

Answer 10

we can simply find the missing angle since we know the sum of triangle is 180 degrees therefore
90+ 49 + x = 180
but not the angles is what they looking for... i believe i can use the sine function to find this.

Answer 11

Well first, find the angles, then find the sides.

Answer 12

And @Will.H I'm sure you can use the sine function to find it, but I learned it not doing that so I may drop out if that's how you'll explain it

Answer 13

do you know the rule that says \[\cos(anglex) = y/s\]
where s is measure of the known sides and measure of angle shouldn't be the right angle measure we should add the other angle. therefore.
\[\cos(49)= s/55\]
and so x= 36 is that make sense? do you know that rule?

Answer 14

not really, what would y be in that? im sorry but youre gonna have to explain it like youre talking to a 10 year old. you might as well be

Answer 15

oh sorry. i might missed up with variables. i meant to add y instead of s in the last step. but not either sure of the answer. so up to you bruh

Answer 16

is it Cos or tan that we should add? @thenicknac

Answer 17

no clue.

Answer 18

we can use the sine function to get the answer which i know she need to understand the way not the answer. but that's what i could do. or really give me another 5 mins. it's been awhile since geometry

Answer 19

alright, i can wait 5 mins

Answer 20

@horsegirl27 i need you here

Answer 21

Sorry idk anything about sine functions

Answer 22

But I may be able to explain it a different way

Answer 23

What we need to use is the pythagorean theorem. Do you know what that is?

Answer 24

i know of it lol

Answer 25

the square of the hypotenuse is the other 2 sides right?

Answer 26

hold on a sec

Answer 27

So do you know that it's a^2+b^2=c^2? That's the first part of understanding it

Answer 28

yes

Answer 29

ik that much i'd hope lmao

Answer 30

Ok good haha. And do you know this? http://prntscr.com/b6wa0b

Answer 31

i do now lol

Answer 32

Ok well good lol

Answer 33

so your hypotenuse on triangle DEF is 55

Answer 34

And so currently you have a^2+b^2=55^2

Answer 35

the answer is 45.51 you can use the way i used in the first place but instead of cos just put tan. that was my mistake. do you agree with this result @horsegirl27

Answer 36

Ummm hold on @Will.H show me your process

Answer 37

after all, @thenicknac does need to understand how you found that

Answer 38

thanks for the answer but, i would to know what im doing so i can complete the other 4 questions without bothering you

Answer 39

would like to**

Answer 40

use the Pythagorean theorem to find if that's correct by substituting one of the legs by 45.51.

Answer 41

Anyway @thenicknac were you still following with what I was saying? Have any of your lessons been mentioning the pythagorean theorem?

Answer 42

yes and im following

Answer 43

Ok good. So next we'll need a^2 so we can find b^2

Answer 44

yes, how i would i go about doing that...

Answer 45

Ok I know this but first let me double check google so i don't misconstrue what I've learned before lol
So just give me a few minutes

Answer 46

alright, take your time

Answer 47

what Geometry course do you take? have you learned about sin, cos, tan?

Answer 48

Let's hope you have because that will make your life so much easier

Answer 49

i have a geography course through Florida Virtual School, and it did teach it but it kinda just flew over my head... Math really isnt my strong suit. i've failed my past 3 classes.

Answer 50

luckily i rememver a song from my geometry teacher at actual school, and that should help lol

Answer 51

because the question can never be found by the Pythagorean theorem. for the Pythagorean theorem there has to be at least 2 known variables. and your mission would be finding the 3rd. HOWEVER in this one, we have to missing legs (sides) so it is impossible to use the Pythagorean theorem. so this question is essentially about sin, cos, tan

Answer 52

Well we can use sohcahtoa to then use the pythegorean theorem can't we?

Answer 53

Sorry if I'm wrong here oops lol

Answer 54

No worries, Pythagorean theorem is no good in this question, you can use it after finding the measure of that side so that you check your answer.

Answer 55

How about you explain sin, cos tan, then I'll explain checking it lol so then i can explain the pythagorean theorem too just in case haha

Answer 56

sine is opposite/hypotenuse, cosine is adjacent/hypotenuse and tangent is opposite/adjacent right

Answer 57

this is the process of answering this question. i can't really explain about sin, cos, tan. because it would take me a whole day. i will give you the process and then you can analyze it.
the rule we must use is
tan(49) = x/55
then solve for x.

that's all i can do, sorry tho.

Answer 58

That's simple enough, thanks

Answer 59

before doing your assignment just have a quick review over the module.. and @horsegirl27 you like the easy jobs? lol

Answer 60

i fanned you BTW

Answer 61

ofc i like the easy jobs @Will.H I'm half asleep lol

Answer 62

oh thank you sm <33

Answer 63

i'm not really half asleep am just about to fall. and your welcome <33

Answer 64

anyway @thenicknac use what Will gave you and solve for x and then I have like 2 minutes but I'll do my best to explain the pythagorean theorem

Answer 65

and i'll go now. wish you 2 the best. bye

Answer 66

thank you for the help will

Answer 67

i'd send you money if i could lol <3

Answer 68

no need give it to my friend @horsegirl27 see you later.

Answer 69

so with the pythagorean theorem you plug in the hypotenuse as c^2 and then your other side you have. Say you're given side a, so plug in for a^2. Then, square those sides and then get the square root of everything so your missing side (a or b) = the answer you got
hopefully that made sense
I can show you with an example if you need it

Answer 70

i would appreciate that

Answer 71

so say you have a right triangle XYZ
remember that image i showed you with sides a b c?
Let's say c, your hypotenuse is 10
and you're given side a which is 6. you need to find b.
so you have
a^2+b^2=c^2
6^2+b^2=10^2
36+b^2=100
b^2=100-36
b^2=64
find the square root of b^2 and 64 and you end up with b=8. So your missing side would be 8.

Answer 72

that actually makes perfect sense, thank you very much

Answer 73

Glad you understand!! You're very welcome :)
Best of luck in completing the rest of your questions and passing your course