Question

Please Help
(Picture in the comments)
Will Fan All Who Help

Answer 1

You have to use the law of cosines:\[c ^{2}=a ^{2}+b ^{2}-2*a*b*\cos C\]a and b are the lengths of two sides of a triangle and C is the angle between a and b. c is the length of other side of the triangle

Answer 2

@Ask_If_Im_A_Ghost how would I put in the formula?

Answer 3

a and b would be your two known sides (in this case 2 and 5). C is the angle between these two side (in this case, Pi/3), then you just plug in.

Answer 4

LIke this?

Answer 5

yes

Answer 6

So how would I solve it?

Answer 7

You plug in 5 for a, 2 for b, and Pi/3 for C

The resulting equation will look like c^2=(5)^2+(2)^2-2*(5)*(2)*Cos[Pi/3]
Where c is the length of the unknown side.

Answer 8

Oh ok, thank you

Answer 9

I got \[c ^{2}= - 1.44975782\]

Answer 10

I got something different.

c^2=25+4-20*Cos[Pi/3]
c^2=29-20*(1/2)
c^2=29-10
c^2=19

Answer 11

I divided by 20 instead of substracting it

Answer 12

*subtracting

Answer 13

Thank you