D= 70 градусов
B = 40 градусов
СBA = 140 градусов
C(x,y)
(x+2)/2 = -4
x+2 = -8
x = -10
(y-1)/2 = 5
y-1 = 10
y = 11
BC = tg 30 * AC tg 30 = 1 / √3 = 0,57735
BC = <span><span><span>
0.57735 *
40 = 23.09401
</span><span> * 52 = 30.02221
</span><span> * 100 = 57.73503
</span><span> * 38 = 21.93931
</span><span /></span></span>