1. **State the problem:** We have a kite-shaped quadrilateral HIJK with angles at I and K given as $123^\circ$ and $105^\circ$ respectively. We need to find the measure of angle $\angle H$.
2. **Recall kite properties:** In a kite, two pairs of adjacent sides are equal. Also, the angles between unequal sides are equal. Here, $HI = HK$ and $IJ = JK$.
3. **Sum of interior angles:** The sum of interior angles in any quadrilateral is $360^\circ$. So,
$$m\angle H + m\angle I + m\angle J + m\angle K = 360^\circ$$
4. **Use kite angle property:** The angles between the pairs of equal sides are equal. Since $HI = HK$, angles at $J$ and $I$ are equal, so
$$m\angle J = m\angle I = 123^\circ$$
5. **Substitute known values:**
$$m\angle H + 123^\circ + 123^\circ + 105^\circ = 360^\circ$$
6. **Simplify:**
$$m\angle H + 351^\circ = 360^\circ$$
7. **Solve for $m\angle H$:**
$$m\angle H = 360^\circ - 351^\circ = 9^\circ$$
**Final answer:**
$$\boxed{9^\circ}$$
Kite Angle 63Dcb6
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