Question

In triangle AC=BC and ACD=140, find angle A?​

Answer 1

angle ACB = 180°-140° (st. line)

angle ACB=40°

Since AC=BC

So, angle ACB= angle ABC (Isosceles ️ property)

=>angle ABC=40°

Therefore,

angle ABC + angle ACB + angle BAC = 180° (angle sum property of a ️)

40°+40° + angle BAC = 180°

angle A = 180° - 80° (angle A=angle BAC)

angle A = 100°

Answer 2

Answer:

70 degree

Step-by-step explanation:

• because angle ACD+ACB= 180 degree
• 140+ACB=180
• ACB=180-140
• ACB=40 degree
• A+B+C =180degree
• A+B+40=180
• let A ,B =x
• 2x =180-40
• 2x=140
• x=140/2=70 degree