Answer:
x = 7
Step-by-step explanation:
This problem can be solved using angular bisector theorem.
It states that if any angle of triangle is bisected by a line , then that line
divides the opposite side of that angle in same proportion as that of two other sides which contain the angle.
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Here one angle is is divided into parts theta
Thus,
using angular bisector theorem
14/21 = 6/3x-12
=> 14(3x-12) = 21*6
=> 3x-12 = 21*6/14 = 9
=> 3x = 12+9 = 21
=> x = 21/3 = 7
Thus, x = 7
