Given: circle o, cd is diameter, chord ab || cd. arc ab = 74°, find arc ca.

Check the picture below.

CD is a diameter, that means the arcCABD = 180°.

since CD and AB are both parallels, the arcs they make are congruents, namely arcCA = arcBD.

let's say arcCA is hmmmm "x".

1     3    

step-by-step explanation:

hopefully im right

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq