Question

in the isosceles triangle ABC , angle A and angle B are equal . Angle ACD is an exterior angle of ∆ ABC . the measures of angle ACB = ( 3x-17)° and the measure of angle ACD =(8x+10)° respectively . find the measure of angle ACB and angle ACD . Also find the measure of angle A and angle B.

Answer 1

Hello !!!!

• <ACB +<ACD = (3x- 17) +(8x+10) = 180, or

• 11x-7 = 180, or

• 11x = 187, or

• x = 17.

• So <ACB =51–17 = 34 °, and <ACD = 136+10 = 146 °

• A = <B = (180–34)/2 = 146/2 = 73 °

• ACB = 34 deg, <ACD = 146 deg, <A =<B = 73 °.