how do i do this? In rhombus ABCD, AB=17 and AC=25.
Well, you've provided us with information. Is there a question associated with this information?
No, that's all the information given.
Right. What is the question? Draw the rhombus? give the angles? Give the side lengths?
ooooh! my bad. find the area
Ah, alright then. So, what all do we know? We know that each side of the rhombus must be the same length (by definition), and this length is 17. We also know a diagnol, 25. Can you think of a way to use this information to find the area?
can i just multiply 17*17? If all the sides are the same.
The sides are the same, but that doesn't give the area. You need to find the other diagnal, or the height of rhombus (if it were laid on it's side).
Just to check, are you familiar with trigonometric functions?
yah, but i fail at them.
Now, they are just references to compare an angle to two different sides of a right triangle, but that's alright. Have you been given any specific formulae concerning a rhombus? (Trying to make sure you do this the way your class wants you to)
Alright, so I'm guessing it isn't fresh, if anything, so I'll just answer.
The area of a rhombus can be found several ways. The most usually is multiplying the two diagonals and dividing by two. So, we have one diagonal, how do we find the other?
If you draw the rhombus and the two diagonals, it becomes a little more clear. Having the two diagonals there, the rhombus becomes four right triangles, something we're a little more comfortable with. Using the sides we know for one of these triangles (12.5 on one side, 17 on the hypotenuse), we can find the angles of the triangle (we only need one).
Once we have this angle, we can find the last side, which corresponds to half of our second diagonal.
So, now we have both diagonals. We multiply them together, divide by two, and we have the area!
Thank you so much!(:
It's my pleasure. Is this clear? If so, is there anything else you need help with?
Very clear. I'm going over the study guide for finals. So I have a few. But I have to go somewhere now. But thank you.
Alright, good luck!
When you know the side and the hypotenuse, (12.5 and 17), why not just find the other side using pythagoras theorem, and double it to get the other diagonal
Oh yah, that works too.!
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