Math Is Fun Forum

Hate Number Theory

Member

Registered: 2015-12-22

Posts: 11

2 trig problems

Points $A$, $B$, and $C$ are on the circumference of a circle with radius 2 such that $\angle BAC = 45^\circ$ and $\angle ACB = 60^\circ$. Find the area of $\triangle ABC$.

In convex quadrilateral $ABCD,$ $\angle A \cong \angle C,$ $AB=CD=180,$ and $AD \ne BC.$ The perimeter of $ABCD$ is $640.$ Find $\cos A.$
http://services.artofproblemsolving.com/download.php?id=YXR0YWNobWVudHMvNC80LzQxMjgyMjQ1ZDczMDBjMDk5M2E1ZGQxODk1MDExZTJkODM1N2NmLnBuZw==&rn=U2NyZWVuc2hvdCAyMDE2LTAxLTI5IGF0IDYuNTcuMzMgUE0ucG5n

Nehushtan

Member

Registered: 2013-03-09

Posts: 957

Re: 2 trig problems

Hi Hate Number Theory.

Please use [ma­th]...[/math] tags, not dollar signs.

Points

,

, and

are on the circumference of a circle with radius 2 such that

and

. Find the area of

.

In convex quadrilateral

and

The perimeter of

is

Find

---

240 books currently added on Goodreads

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 2 trig problems

Hi;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: 2 trig problems

hi Hate Number Theory

http://www.mathisfunforum.com/viewtopic.php?id=22508

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob