ΔTIC is an isosceles triangle with vertex angle I. Find the measures of the base angles of ΔTIC if m∠I = 100º.
1 answer
Since triangle ΔTIC is an isosceles triangle, we know that the base angles are congruent. Let the measure of each base angle be x. The sum of the measures of the angles in any triangle is 180º, so we can write the equation 100 + x + x = 180. Simplifying the equation gives 100 + 2x = 180. Subtracting 100 from both sides gives 2x = 80. Dividing both sides by 2 gives x = 40. Therefore, each base angle measures 40º.