Question

Find the value of a

Answer 1

eww, looks like a law of cosines. I forget that off the top of my head. GOOGLE :D

Answer 2

\[a ^{2}+8^{2}=11^{2}\]
a=sqrt 57
a=7.549834
a=8
????????????

Answer 3

This would be a problem where the most effective approach would be the Law of Cosines (quite possibly the only)

Answer 4

you can't use Pythagorean theorem because it is not a right triangle.

Answer 5

Law of Cosines is
\[a^2 = b^2 + c^2 - 2bc*cos(A)\]
where a, b, and c are your side lengths, A is the angle opposite the side a.

Answer 6

\[a^{2}=8^{2}+11^{2}-2(88)*32.2\]

Answer 7

I'm not on the right track. It doesnt really make sense to me.

Answer 8

that should be cos(32.2) but other than that you are correct.
What part of it isn't making sense to you?

Answer 9

a=6

Answer 10

It didnt make sense because I forgot the cos!!! A simple mistake messes me all up! =) Thank you so much

Answer 11

a^2 + 8^2 =11^2
a^2 +62=121
a^2 =121-64
a^2=57
a=sqrt57
a=7.54....

Answer 12

No problem :)

Answer 13

Now I do not know if it is 6 as I thought or 8 as hexagon listed =( I think hexagon used the theorem that I did at first, which is not right. @blarghhonk8 ?????

Answer 14

The law of cosines answer would be correct. Which would be 6. Pythagorean's Theorem, which while succinct, awesome, and frequently appearing, is ONLY applicable to right triangles.

(I suppose you could argue that it is applicable to non-right triangles in that it can be used to determine if a triangle is a right triangle, obtuse, or acute if you know all of the side lengths. But it beyond that it can only be used to find the side lengths of right triangles.)

Answer 15

THANK YOU! This makes a lot of sense in your words.