70
85 degrees
It would be (90) - (1/2 of the vertex angle)
Congruent angles.
35 and 110 degrees (180 degrees in a triangle)
Two angles that are congruent have the same angle measurement.
That means they have the same measurement. Any two angles that have the same measurement (for example, in degrees) are said to be congruent.
A polygon that all sides and angles are the same measurement is a regular polygon.
If the heptagon is regular the angle measurement for three angles would be approximately 385.7
The vertex angle of an isosceles triangle is equal to the measure of each of its base angles. Therefore, if one of the base angles measures 42 degrees, then the vertex angle also measures 42 degrees.
Base angles.
They are supplementary angles.
the sum of the measures of the interior angles of any triangle equals 180*. the two base angles in an isoceles triangle are equal to each other so if you have the measure of one of the two base angles, then you know the other. so for example, if one base angle equals 36, then the equation to find the missing angles would be 36+36+x=180 when solved x=108, which would be the non base angle