Step-by-step explanation
The sum of the three internal angles of a triangle is always equal to 180°. Let's use x for the measure of each of the missing angles. Then the sum of the three angles of triangle ABC is expressed as x+x+100°=2x+100°. If we equalize this expression to 180° we obtain an equation for x:
We can substract 100 from both sides of the equation:
Then we divide both sides by 2:
Answer
Then the answer is 40.