Answer:
A. 13
Explanation:
The non-vertex angles of a kite are always congruent. Therefore,
m<X = m<Z = 102°
Sum of all angels of a kite = 360°
Thus:
m<X + m<Y + m<Z + m<W = 360°
Substitute
102 + (5x - 4) + 102 + (7x + 4) = 360
102 + 5x - 4 + 102 + 7x + 4 = 360
Add like terms
204 + 12x = 360
12x = 360 - 204
12x = 156
x = 156/12
x = 13