Answer:
x = 5
Explanation:
in ΔABC , AB = BC , hence triangle is isosceles, thus
∠A = ∠C = 73° ( base angles are equal )
the sum of the 3 angles in a triangle = 180°
subtract the sum of the base angles from 180 for ∠B
∠B = 180° - (73 + 73)° = 34°
⇒ 6x + 4 = 34 ( subtract 4 from both sides )
6x = 30 ( divide both sides by 6 )
x = 5