Step-by-step explanation:
Given Angle CBD = 30,
Angle ABC + Angle CBD = 180 (Sum of Angles on the same straight line)
Angle ABC + 30 = 180
Angle ABC = 180 - 30 = 150
Since Angle AB =~ BC,
Angle A = Angle C
Let angle A and C be x.
Angle A + Angle C + Angle ABC = 180 (Sum of Angles in a triangle)
[tex]x + x + 150 = 180 \\ 2x + 150 = 180 \\ 2x = 180 - 150 \\ 2x = 30 \\ x = 15[/tex]
Therefore Angle A = 15 degrees
