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Consider the triangle DAB, with |DA|=9 ft, |AB|=23 ft and m(DAB)=80°.
To find the length of the diagonal, |DB|, we use the cosine law:
Thus, |DB|=
(ft)
Answer: 24.6 ft
Consider the triangle DAB, with |DA|=9 ft, |AB|=23 ft and m(DAB)=80°.
To find the length of the diagonal, |DB|, we use the cosine law:
Thus, |DB|=
Answer: 24.6 ft