Answer:
x = 8
Explanation:
from the figure we understand that it is an isosceles triangle, therefore 2 sides and two congruent angles, BD and CD are congruent, therefore 3x = x + 16.
let's solve
3x = x + 16
2x = 16
x = 8
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check
3 × 8 = 8 + 16
24 = 24
thee answer is good