Question

Circle E, and are diameters. Angle BCA measures 53°.

Answer 1

Answer:

74°

Step-by-step explanation:

see the attached figure to better understand the problem

we know that

Triangle EBC is an isosceles triangle (because has two equal sides EB=EC)

so

$m\angle BCA=m\angle BCE=m\angle EBC=53^o$

Find the measure of angle BEC

Remember that the sum of the interior angles in any triangle must be equal to 180 degrees

so

$m\angle BCE+m\angle EBC+m\angle BEC=180^o$

substitute the given values

$53^o+53^o+m\angle BEC=180^o$

$m\angle BEC=180^o-106^o=74^o$

Find the measure of angle AED

we know that

$m\angle AED=m\angle BEC$ ----> by vertical angles

so

$m\angle AED=74^o$

Find the measure of arc AD

we know that

$m\ arc\ AD=m\angle AED$ -----> by central angle

therefore

$m\ arc\ AD=74^o$

Answer 2

Answer:

The answer is B on Edge 2020`

Step-by-step explanation:

I did the exam