How do I find the area of this parallelogram? (lateral side 9cm, bases 12cm, angle 73*)

chijioke said:
Welcome back!

It doesn't help me in any way as long as the area of the parallelogram cannot be found with the given information.
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But YOU don't know that. You stopped in the middle of the problem because someone told you that you can't solve the problem and then you have an attitude.
You, not some helper on the former, must conclude on your own that the problem can't be done. You had so much information that you failed to label. You need to understand that your diagram was unfinished.
 
chijioke said:
I would not know how to find the area because the height or included [angle] is is not given. Do you have any clue as to how to go about it?
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It's a bad problem, as I think you know, and have been told repeatedly. Here is a possibly improved image:

1681955306147.png

It certainly doesn't appear that the 1.5 cm is intended to be an altitude (height); it's not even clear that this is a parallelogram, except that they say it is, so you're right not to make any assumptions about the height.

All we can really say, unless they told us the 1.5 cm was the altitude, is that the altitude is less than 1.5 cm, so the area is less than 27 cm2. I have no idea what they expected you to use the 1.5 cm for!

Just state that you understand that the problem as given can't be solved, and this thread will be finished. Don't let Steven make you think there's more to do.
 
Steven G said:
Look at how much information you failed to list. It is reasonable to assume that with this missed information you could have solved the problem.
Adjacent angles in a parallelogram are supplementary!

View attachment 35609
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How does that help us find either x or y???? ?
(And thence the height or area of the parallelogram.)
 
The Highlander said:
How does that help us find either x or y???? ?
(And thence the height or area of the parallelogram.)
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In the end, it doesn't.
Here is my issue.
Yes, when a mathematician looks at this problem they have enough experience to just say--it's not solvable. Now either they considered the angles I mentioned or just knew that the angles would not help.

I doubt that the OP is a mathematician. That is, I think that @chijioke, needs to make extra sure that the problem can't be solved compared to a seasoned mathematician. Mathematician just have that gut feeling and an enormous amounts of theorems to recall on when needed.
I just want the best for the op and getting them to think never hurts. This time maybe the op was lucky because the problem could not be done, but what about the other times when in fact there was enough information to find the height of the parallelogram and the op had no idea how to find it.
Just remember, this is a help forum.
 
Steven G said:
In the end, it doesn't.
Here is my issue.
Yes, when a mathematician looks at this problem they have enough experience to just say--it's not solvable. Now either they considered the angles I mentioned or just knew that the angles would not help.

I doubt that the OP is a mathematician. That is, I think that @chijioke, needs to make extra sure that the problem can't be solved compared to a seasoned mathematician. Mathematician just have that gut feeling and an enormous amounts of theorems to recall on when needed.
I just want the best for the op and getting them to think never hurts. This time maybe the op was lucky because the problem could not be done, but what about the other times when in fact there was enough information to find the height of the parallelogram and the op had no idea how to find it.
Just remember, this is a help forum.
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But computing those angles doesn't help determine that the problem can't be solved!

The help that was needed here was to confirm the OP's sense that there was not enough information:
chijioke said:
I continue. But what if I am given this parallelogram
I would not know how to find the area because the height or included [angle] is is not given. Do you have any clue as to how to go about it?
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If you want to prove that there really is not enough information, calculating (or even trying to calculate) the angles won't help. What does help is showing that by varying the angle of the slanted line, you can get different heights, and therefore different areas, without violating the conditions of the problem. So provide a hint in that direction.
 
Dr.Peterson said:
If you want to prove that there really is not enough information, calculating (or even trying to calculate) the angles won't help. What does help is showing that by varying the angle of the slanted line, you can get different heights, and therefore different areas, without violating the conditions of the problem. So provide a hint in that direction.
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What you say is true but can the op figure that out.
All I am saying is that before you just say that the problem can't be done you need to investigate what is going on. This is what math is all about and as a mathematician you know this true.
I tell my students never to believe what I tell them. Rather they should go home and convince themselves that what I am saying in class is true or not.
 
Dr.Peterson said:
It's a bad problem, as I think you know, and have been told repeatedly. Here is a possibly improved image:

View attachment 35610

It certainly doesn't appear that the 1.5 cm is intended to be an altitude (height); it's not even clear that this is a parallelogram, except that they say it is, so you're right not to make any assumptions about the height.

All we can really say, unless they told us the 1.5 cm was the altitude, is that the altitude is less than 1.5 cm, so the area is less than 27 cm2. I have no idea what they expected you to use the 1.5 cm for!

Just state that you understand that the problem as given can't be solved, and this thread will be finished. Don't let Steven make you think there's more to do.
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You are on point.
 
Steven G said:
I tell my students never to believe what I tell them. Rather they should go home and convince themselves that what I am saying in class is true or not.
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And how many students will have that time? At times you end up putting the students in more trouble by saying that. You know they resort to you as the final help.
 
chijioke said:
And how many students will have that time? At times you end up putting the students in more trouble by saying that. You know they resort to you as the final help.
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They also know that what I'm teaching them is correct. How can one keep accepting more and more about math and not understanding it?
 
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