Shorter diagonal: the angle between sides 3 and 5 is 50º (SD for short diagonal)
SD^2 = 5^2 + 3^2 - 2(5)(3)cos 50º
take it from there.
Let me know what you get for the equation of the longer diagonal.
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A parollelogram has side lengths 3 and 5, and one angle is 50 degrees. Find the lengths of the diagonals.
5 answers
I got 3.8, we round to the nearest tenths.
3.8 was my answer for the short diagonal.
I'm not sure how to find the long diagonal.
I'm not sure how to find the long diagonal.
for the longer, same sides except the angle between them is now 130º
LD^2 = 5^2 + 3^2 - 2(3)(5)cos130
= 25 + 9 - 30(-.642788)
= 7.2996
= 7.3
Notice this time the last term was actually added because of the double negatives.
LD^2 = 5^2 + 3^2 - 2(3)(5)cos130
= 25 + 9 - 30(-.642788)
= 7.2996
= 7.3
Notice this time the last term was actually added because of the double negatives.
last two lines should have been
LD = 7.2996
= 7.3
(I still had it equal to LD^2)
LD = 7.2996
= 7.3
(I still had it equal to LD^2)