Question

in the diagram below, AB and BC are tangent to O. what is the measure of ADC?

Answer 1

For the given question above, here is the solution for it:

(x - 140)/2 = 40

 x- 140 = 40*2

 x - 140 = 80

 x = 80 + 140
 
 x = 220

The answer is 220. I hope this helps.

Answer 2

Given AB and BC are tangent to O .The question is asking us to find measure of major arc ADC.In the figure the measure of minor arc AC is given as 140 degrees.

Sum of measure of arcs in any circle is 360 degrees.

In the figure measure of minor arc + major arc = 360

Substituting the measure of minor arc AC we have:

140+ measure of arc ADC=360

Subtracting both sides by 140 we have:

Measure of arc ADC= 360-140=220 degrees.