Respuesta :

use pythagorean theorum: c^2 = a^2 + b^2, where BC = c, AB = a, AC = b
so b^2 = c^2 - a^2 --> b = SR(c^2 - a^2), where SR means square root of ( )
b = SR(64 - 49) = SR(15) = 3.873 = B) 3.87 units

Answer: 3. 87 units mate

Step-by-step explanation: