Answer:
y = 12
Explanation:
Congruent Triangles:
ABC and CBD are congruent triangles because:
* They have one right angle.
* They share one side
* They have one congruent angle (BD is the bisector of triangle ABC)
This implies that sides AD and DC have the same length, thus:
3y + 6 = 5y - 18
Subtracting 6:
3y = 5y - 18 - 6
Subtracting 5y:
3y - 5y = - 18 - 6
Simplifying:
-2y = -24
Dividing by -2:
y = -24 / (-2)
y = 12