Answer: 23.7
Step-by-step explanation:
Let's calculate the acute angle at the base of the triangle:
180° - 90° - 40° = 50°
Find side x:
[tex]\dfrac{sin \: 90^{o} }{31} =\dfrac{sin \: 50^{o} }{x}\\\\sin \: 90^{o} \cdot x=sin \: 50^{o} \cdot 31\\\\sin \: 90^{o} =1\\sin \: 50^{o} \approx 0.766\\1 \cdot x =0.766 \cdot 31\\x=23.746\\23.746 \approx 23.7[/tex]
