Respuesta :

Juannova17
Use trigonometric ratios.
Use angle(19)
Adjacent side of angle measure 19 is X
The hypotenuse is 21.
Use the cosine
Cos(19)=x/21

Plug in calculator
(21)cos(19)=19.85

Round to the nearest tenth. Which means the 8 rounds up to 9.

Answer: 19.9