(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Parallelograms 5cm side is located on a plain alpha and its 3cm side forms an angle with the plain equal to 30 degrees. Find the area for the parallelograms projection on the plain alpha, if an angle in the original parallelogram is 60 degrees.

2. Relevant equations

all kinds

3. The attempt at a solution

I think Im visualizing something wrong. Because what I did gave me an answer or 11,25 cm^{2}, but the answer is supposed to be 10,6cm^{2}according to the textbook.

Here's what I did:

Find the length of the 3cm side's projection on the plain: d=3cm*cos30=3*sqrt3/2 cm

Directly find the area of the projection with 2 sides of the projection and the angle between them: S=5*d*sin60=5*3*sqrt3*sqrt3/2*2=11,25 cm^{2}

Where did I go wrong?

Thanks in advance,

fawk3s

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# Parallelograms projection on a plain

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