Question

In the diagram, point O is the center of the circle and angle ADB = 43°. If angle AOB = angle BOC, what is angle BDC?

Answer 1

A-45
B-43
C-41
D-37
E-33

Answer 2

So, first you should know the rule that:

The angle on the circumference is half of that on the Center.
Which means...

Answer 3

So,
Angle AOB =
\[43 \times 2\]
\[Angle AOB = 86\]

Answer 4

If angle AOB = and BOC
This means,
BOC = 86

Answer 5

NOW, we will find the Angle AOC
This, we find by adding AOB and BOC
86 + 86 = 172

Angle AOC = 172

Now as I already said that the Angle on the circumference of the Circle is half of that on the Center. This means Angle ADC...
Angle ADC = 172/2
Angle ADC = 86

Now...
Angle ADC - Angle ADB = Angle BDC

ADC = 86
ADB = 43

So,
86 - 43 = BDC
Angle BDC = 43

Answer is: Angle BDC is 43 which means it's Option "B"

Answer 6

Got it?

Answer 7

yes, thank you so much for the help completely understand it

Answer 8

You're Welcome! :)