Question

help please!!!
In Angle ABC, C is a right angle. Find the remaining sides and angles. Round your answers to the nearest tenth.
a = 3, c = 19

A. M 13 years ago

Answer 1

@jim_thompson5910 can you help me with this?

Answer 2

to find b, you use this equation

a^2 + b^2 = c^2

so you would plug in a = 3 and c = 19, then solve for b

Answer 3

is b 11.6?

Answer 4

let me check one sec

Answer 5

no it's a bit too small

Answer 6

because i got 135 after doing 3^2=9 and 19^2 =144 then subtracted the two

Answer 7

hmm i must have made a mistake somewhere then :/ let me check.

Answer 8

i got 361 after doing 19^2 i see my mistake :)

Answer 9

no worries, silly mistake

Answer 10

so what do you get for b now?

Answer 11

i got 18.7 this time.

Answer 12

which would round to 18.8

Answer 13

same here

Answer 14

angle A can be found by

tan(A) = opp/adj

tan(A) = 3/18.8

A = arctan(3/18.8)

Answer 15

okay so the choices are between b and c

Answer 16

because angle a cannot be larger than angle b correct?

Answer 17

A is the smaller angle, yes

Answer 18

im sorry i meant to say between A and C

Answer 19

is the correct answer A?

Answer 20

tan(B) = opp/adj

tan(B) = 18.8/3

B = arctan(18.8/3)

B = ??

Answer 21

i dont understand any of that.

Answer 22

do you have a calculator?

Answer 23

yes , i do.

Answer 24

and have you covered inverse trig functions?

Answer 25

ok you would type in

2nd

then the "tan" button

then type in 3/18.8 and close off the parenthesis

then hit enter

Answer 26

no , this is supposed to be an algebra class but the work is trig and none of it has been covered.

Answer 27

sounds like a very mixed up class to me

Answer 28

i got 0.159?

Answer 29

yeah i have complained several times but nothing was done about it.

Answer 30

make sure you're in degree mode

Answer 31

you are currently in radian mode at the moment

Answer 32

i see, so they don't care that you haven't had the proper prerequisite classes at all?

that's not good

Answer 33

i don't know how to put my calculator in degree mode :/

Answer 34

it says DEG at the top of my screen i'm guessing thats it?

Answer 35

you have a TI calculator right?

Answer 36

yes hit that button or option

Answer 37

yes, TI-30Xa

Answer 38

ok now try it again and tell me what you get

Answer 39

i got the same thing ..

Answer 40

it says it's in degree mode but keeps giving me that same answer for some reason

Answer 41

hmm frustrating, idk why that's happening, i'm sry

anyways, you can use google as a calculator

if you type in "arctan(3/18.8) in degrees" without the quotes, you'll get this result

http://www.google.com/search?hl=&q=arctan%283%2F18.8%29+in+degrees&sourceid=navclient-ff&rlz=1B3GGLL_enUS420US420&ie=UTF-8

Answer 42

see how it says

"arctan(3 / 18.8) = 9.06650274 degrees"

so this rounds to 1 decimal place to get 9.1 degrees

so A = 9.1 degrees

Answer 43

so that would round to 9.1 :)

Answer 44

so that means the answer is a then?

Answer 45

yep

Answer 46

you got it

Answer 47

thank you!! and yes i understand that part of it now.

Answer 48

ok that's great