ABCD Is quadrilateral inscribed in a circle such that BC =9cm ,BA=7.2cm,CBA=51 and ACD=29 calculate angle AC

1 answer

To find angle AC, we need to use the property of an inscribed angle.

An inscribed angle is half the measure of the arc it intercepts.

Since ABCD is inscribed in a circle, we can see that angle ADC is the intercepted arc for angle AC.

Thus, angle AC = 2 * angle ADC.

Now, let's find angle ADC.

We know that angle DCA = angle DCB = 180 - angle CBA = 180 - 51 = 129 degrees.

Since ABCD is a quadrilateral, the sum of all interior angles is 360 degrees.

Thus, angle ADC + angle DCA = 360 degrees.

Substituting the values we know, we have:

angle ADC + 129 = 360

Subtracting 129 from both sides, we get:

angle ADC = 231 degrees.

Finally, substituting this value into our initial equation, we have:

angle AC = 2 * 231 = 462 degrees.

Therefore, angle AC is equal to 462 degrees.