Question

Find the length of a if the measure of angle A equals 50 degrees, b = 20, and c = 25. Show work. Round answer to the nearest hundredth.

Answer 1

well, you have angle "A", and it's facing off side would be "a"
you also are given sides "b" and "c"

"b" and "c" most likely converge in the angle that IS NOT "B" or "C", meaning, "A"

so you have and angle and its 2 adjacents sides

Answer 2

so :), what do you think?

Answer 3

Okay so, you use the law of cosine

Answer 4

yeah

Answer 5

pretty straightforward, just plug in the numbers

Answer 6

\[50^{2} \left( 20^{2} + 25^{2}\right) -2\left( 20 x 25 \right)\]

Answer 7

like that?

Answer 8

or would the 50 be cos(50) at the end

Answer 9

\(\large
\color{green}{a}=\sqrt{\color{blue}{b}^2+\color{red}{c}^2-2(\color{blue}{b}\times\color{red}{c})cos(\color{green}{A})}
\)

Answer 10

Oh okay

Answer 11

It came out negative again. Agh

Answer 12

What did I do wrong? I know thats not the answer

Answer 13

make sure your calculator is in Degrees mode

Answer 14

it is

Answer 15

lemme recheck

Answer 16

I get a positive number :)

Answer 17

lemme try afgain

Answer 18

5?

Answer 19

ha.

Answer 20

5? ahemm, a bit of a small side, is a bit bigger

Answer 21

oops forgot to add in cos

Answer 22

it came out with -610

Answer 23

ahhhhh

Answer 24

heheh

Answer 25

let's see

Answer 26

what is wrong with me

Answer 27

I typed it in exactly the same

Answer 28

√ (20^2+25^2) -2 (20x25) cos(50)

Answer 29

$$\large{
20^2+25^2=1025\\
2(20\times 25)=1000\\
cos(50^o)=0.64}
$$

Answer 30

so, what do you get?

Answer 31

2023.64

Answer 32

44.9

Answer 33

45! YAY

Answer 34

hehee, you may wan to recall the "order of operations" for numbers :)

Answer 35

Oh yeah...ha. So not 45?

Answer 36

if one leg is 20 and the other 25, another side of 45, would yield an angle bigger than 50 degrees

Answer 37

I assume you know the "order of operations"?

Answer 38

http://www.webquest.hawaii.edu/kahihi/mathdictionary/images/PEMDAS.png

Answer 39

yeah pemdas

Answer 40

1025-(1000*0.64)

Answer 41

385?

Answer 42

but now I need to square root it, correct? Or no

Answer 43

yes

Answer 44

which would be 19.6

Answer 45

yep

Answer 46

YAY