Respuesta :

Step-by-step explanation:

The sum of co-interior angle = 180°

Now,

2x + 7x = 180°

9x = 180°

x = 180° ÷ 9

x = 20°

Answer:

x = 20

Step-by-step explanation:

Co-interior angles (also called same-side interior angles) are two angles that are on the same side of the transversal and on the interior of (between) the two parallel lines.

Same-side interior angles theorem:  If two parallel lines are cut by a transversal, then the same side interior angles are supplementary (add up to 180º).

Therefore, if 2x and 7x are co-interior:

⇒ 2x + 7x = 180

⇒ 9x = 180

⇒ x = 20