Question

in figure AB is equal to AC and Angle ACD is equal to 120 degree find angle A

Answer 1

in triangle ABC,

AB=AC implies that ABC is an isoceles triangle

let one of its equal angle be x then ,

x +x+∠A = 180°  ( ANGLE SUM PROPERTY )

⇒ 2x + ∠A = 180° ...... EQ.1

ALSO ,∠A+x = 125°    (EXTERIOR ANGLE PROPERTY )

MULTIPLYING THE ABOVE EQUATION BY 2 WE GET ,

2∠A+2x = 250° ......... EQ. 2

SUBTRACTING EQ. 1 FROM EQ.2 ,

2∠A + 2x -2x -∠A= 250°-180°

⇒∠A = 70°

HOPE IT HELPED !

Answer 2

Can you check this question again I guess it is kind of wrong or you can tell me if the figure is like this
If the figure is like this then
Since angle ACD is 120° then Angle ACB =60°
And then angle A will also be 60°.