Answer:
70°
Step-by-step explanation:
We know that the triangle is an iscoceles based on the 2 small lines drawn horizontally on 2 sides of the triangle.
We know that the base angles in an iscoceles triangle are the same, so the angle that has not been drawn is 55°.
55° + 55° = 110°
180° - 110° = 70° (180 comes from the entire triangle adding up to 180°)
