Question

In the triangle ABC the angles are in the ratio 3:4:5 In the order, the exterior angle formed when BC is extended​

Answer 1

Answer:

3x+4x+5x=80

12x=180

x=180÷12

x=15

3×15=45

4×15=60

5×15=75

the exterior angle will be 3x+4x

45+60=105

Answer 2

Step-by-step explanation:

let angles of triangle ABC be 3x 4x and 5x

where,A=3x,B=4x and C=5x

A+B1C=180 (being sum of angle of triangle)

3x +4x +5x =180

12x =180

x =180/12

x =15

• 3x=3×15 =45
• 4x=4×15 =60
• 5x=5×15 =75

here ,

• A + B = Angle ACD ( BC is extended to D )
• 45 + 60 =105