Points D, B, and E are collinear. Find the value of a so that points A, B, and C
are collinear.

Answer: x = 14
Step-by-step explanation:
For points A, B, and C to be collinear, angle ABD and EBC must be vertical angles. Vertical angles are congruent so we will set them equal to each other and solve for x.
Given:
126 = 9x
Divide both sides of the equation by 9:
14 = x
Reflexive property:
x = 14