Respuesta :

Answer:

91°

Step-by-step explanation:

The answer is 91°. What you do is you name the angle next to 89° with x, and you know that an angle whose arms are horizontal makes 180°. So, you go:

180°=x+89°

x=180°-89°

x=91°.

Now, there is this rule that says that when two angles are on sides like x and ? are, then they are equal. Therefore, the angle marked with ? is 91°.