Question

the exterior angle ACD of a triangle ABC is 105 degree angle b is equal to 70 degree find angle A is angle ACD greater than angleA find angle ACB also

Answer 1

Here it is...
This us your solution of your question...

Answer 2

As, two opposite angle of a triangle =1 exterior angle
Therefore, angle B + angle A = angle ACD
70°+angle A = 105°
Angle A= 105-70 = 35°
Now,
Angle (A+B+C)= 180°
70+35+angle C = 180
angle C =180-70-35
Angle C = 180-105 = 75°
Therefore, angle ACB = 75°