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