Find Area of Rhombus

What is the area of rhombus ABCD if AB = 13 inches and AC = 10 inches?

I was told to use the formula:

A = 1/2 TIMES (diagonal one * (diagonal two)) However, I cannot find the right answer. Help....

In a rhombus, the diagonals are perpendicular bisectors.

1) Draw the rhombus.
2) Draw a diagonal.
3) Label the measure of all four edges: 13 <== Definition of a rhombus.
4) Label the measure of the drawn diagonal: 10
5) Draw the other diagonal.
6) Mark all four central angles as right angles. <== Perpendicular
7) Label the measure of each piece of the first diagonal: 5 <== It's a bisector, so half is on each side.
8) Note that you now have four 5-???-13 Right triangles.
9) You can use the Pythagorean Theorem or maybe you already memorized that the other side is 12.
10) Label the measure of both pieces of the other diagonal: 12
11) Label the measure of the entire other diagonal: 24 = 12 + 12 <== Bisector again.

Now you have the measures of both diagonals. Almost done...

hi. i actually was doing those about a week ago. yes the formula for that is 1/2 diagonal 1 * diagonal 2.

haha, dis-regard what i had previously written here!

That may be the correct solution, but as the problem is presented, 13 isn't a diagonal. It's an edge.

mmm.... didn't notice that part

alright, i see what we're doing here now. so, do just as tk said, and you will have the measure of the other diagonal. NOW is where you use the formula A=1/2 (d1)(d2) ~right tk? :wink: ~ so, plug into the equation! A=1/2 (24)(10) and what do you get?

Hey

Thank you guys.

To tkhunny:

I thank you for taking time out to type very detailed replies to all my questions. I am learning plenty from your notes and truly appreciate your help without complaining like member happy. Member happy obviously would like me to run away from the site, which I am not going to do unless I am told to do so by Ted.

Well, don't go picking on "happy". So far, it appears we are all in this together. We all need a little of the "thick skin" PKA was talking about. That does NOT mean insensitivity or cruelty. It means resilience and understanding. Occasionally, we all write things that aren't quite what we intended. Occasionally, we all take things not quite as they are intended. (For example, when three people respond to your post and you thank only two of them. Do you mean to offend the third? I'm guessing you really don't intend to do that.) If we all decide, up front, that none is being deliberately offensive (whether or not some do try to be offensive), there is a whole lot less to worry about and we can all get along just fine.

You have to do your part. Keep showing us more of your work. We have no idea how, or if, you are progressing unless you give us something. Start setting up those problems. Define your terms. Write down what the problem statement says in terms of those definitions. That will get you started much of the time.

"happy" is not picking on you the way you state;
he suspects that you're the former greatwhiteshark and others...

If you go back and look at some of greatwhiteshark's posts,
you'll see they are "a bit" similar to yours...

BUT just a bit; I'm personally fairly sure by now you're YOU.

You state California as residence: why don't you describe something
in California in a way that shows "you're there": that should make
"happy" happy again !

hey

Denis,

Who really is anybody?