Answer:
Option (1)
Step-by-step explanation:
Properties of the angles of a rhombus:
1). Diagonals are perpendicular.
2). Opposite angles are equal in measure.
3). Diagonals bisect the angles at the vertices.
Given: m∠GJH = 18°
In ΔGJH,
m∠GJH + m∠GHJ + m∠JGH = 180°
m∠GJH + m∠GJH + m∠JGH = 180° [Since, ∠GJH ≅ ∠GHJ diagonals bisect the opposite angles and opposite angles are equal in measure]
2m∠GJH + m∠JGH = 180°
2(18)° + m∠JGH = 180°
m∠JGH = 180° - 36°
= 144°
Since, opposite angles of a rhombus are equal,
m∠JGH = m∠JIH = 144°
Option (1) will be the answer.
