Given b=4 and ∠β=20°,
a = 10.98991
c = 11.69522
∠α = 70° = 1.22173 rad = 7/18π
h = 3.75877
area = 21.97982
perimeter = 26.68513
inradius = 1.64735
circumradius = 5.84761
a
b
c
Calculation Steps
The following is one way to perform the calculation. It may not be the best way.
c =
b
sin(β)
= 11.69522
a = √c2 - b2
= √11.6952176006522 - 42
= √120.77811472661
= 10.98991
∠α = 90° - ∠β
= 70° = 1.22173 rad = 7/18π
area =
a × b
2
=
10.989909677818 × 4
2
= 21.97982
perimeter = a + b + c
= 10.989909677818 + 4 + 11.695217600652
= 26.68513
inradius =
a × b
a + b + c
=
43.959638711274
26.685127278471
= 1.64735
circumradius =
c
2
=
11.695217600652
2
= 5.84761
- ror