Mark is asked to prove that ∠4≅∠6, given that AB∥CD, as shown in the diagram above. Mark's proof is shown in the table below.

Which reason supports the statement Mark made in step 2 of his work?

A
Vertical angles are congruent.

B
Supplementary angles are congruent.

C
Corresponding angles formed by parallel lines are congruent.

D
Alternate interior angles formed by parallel lines are congruent.

D). Alternate Interior Angles formed by parallel lines are congruent.

Step-by-step explanation:

(2x + 16) + (x) = 180

step-by-step explanation:

given,

abcd is a quadrilateral inscribed in a circle

angle a is labeled x plus 16, (x + 16)

angle b is labeled x degrees, (x)

angle c is labeled 6x minus 4, (6x – 4)

angle d is labeled 2x plus 16, (2x + 16)

what equation can be used to solve for angle b?

we know that the sum of the opposite angles of a simple quadrilateral inscribed in a circle is 180 degrees.

angle b is opposite angle d

therefore, angle b + angle d = 180

(x) + (2x + 16) = 180 

same as (2x + 16) + (x) = 180