Point B is the center of a circle, and AC is a diameter of the circle. Point D is a point on the circle different from A and C. If angle BDA = 20 degrees, what is the measure of angle CBD? Answer choices: a) 70 degrees b) 20 degrees c) 120 degrees d) 140 degrees e) 40 degrees

Respuesta :

BA and BD are radii of the circle, so triangle ABD is isosceles. Then angles BDA and BAD are congruent, and the remaining (central) angle ABD has measure

[tex]m\angle ABD=(180-2\cdot20)^\circ=140^\circ[/tex]

Angles ABD and CBD are supplementary, so

[tex]m\angle CBD=(180-140)^\circ=40^\circ[/tex]

and the answer is E.

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The measure of the angle CBD is 40°.

What is a circle?

A circle is a round-shaped figure that has no corners or edges. In geometry, a circle can be defined as a closed, two-dimensional curved shape.

According to the given problem,

BA and BD are radii of the circle.

Triangle ABD is isosceles.

Angles BDA and BAD are congruent.

m∠ABD = (180 - 2*20)

              = 140°

Angles ABD and CBD are supplementary, so,

∠CBD = 180 - 140

           = 40°

Hence, the measure of the angle CBD is 40°.

Learn more about circles here: https://brainly.com/question/11833983

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