Mathematics Question and Solution
Notice.
The ascribed triangle is isosceles with angles 70°, 70° and 40°.
Let the two equal lengths be 1 unit.
(1/sin70) = (a/sin40)
a = (sin40/sin70)
a = 0.6840402867 units.
sin40 = b/a
sin40 = b/0.6840402867
b = 0.4396926208 units.
c² = 0.5²+0.4396926208² -2*0.5*0.4396926208cos20
c = 0.1736481777 units.
It implies, the required angle x is;
(0.1736481777/sin20) = (0.4396926208/sinx)
x (required angle) = 60°
