Respuesta :

Answer: 537

Step-by-step explanation:

Given: a = 640 A =70° B =52°

Whenever two angles and one side of a triangle is given, we can always use the sine formular to find the other side

Using the sine formula;

sin A / a = sin B /b

sin70° / 640 = sin 52° / b

cross multiply

bsin70° = 640sin52°

To get b, we divide bothside by

sin 70°

b = 640sin52° / sin 70°

b = 504. 327 / sin70°

b = 536. 693

b = 537 to the nearest whole number