Solution 4.2:1d
From Förberedande kurs i matematik 1
The side marked \displaystyle x is the hypotenuse in the right-angled triangle and the side of length \displaystyle \text{16} is the adjacent to the angle of \displaystyle \text{2}0^{\circ }.
By writing the quotient for
\displaystyle \text{cos20}^{\circ }, we obtain the relation
\displaystyle \text{cos20}^{\circ }=\frac{16}{x}
and this gives
\displaystyle x=\frac{16}{\text{cos20}^{\circ }}\quad \left( \approx 17.0 \right).
