Question

Помогите решить задания

Answer 1

1)
ВЕ/АВ = cos(30)
CF=BE=AB*cos(30) = 4 * (1/2) * √3 = 2*√3

2)
AB=BC=AC=a
∠A = ∠C = ∠ABC = 60
BD/BC = sin(60)
BD=BC*sin(60) = a * (1/2) * √3