Answer:
81°
Explanation:
the sum of the interior angles of a triangle is 180°.
The base of the 10 triangles make a straight line. 180/10 = 18°
The small angle along the base is 18°
180-18 = 162
The other two angles of the triangle must add up to 162. Since this is a isosceles triangle. The other 2 angles have the same measurements.
162/2 = 81. The measurement of the angle we are looking for is 81°