Question

12. In a right-angled triangle, the ratio of the angles other than right angle is 5: 4. What are the angles?

13. In an isosceles triangle, each base angle is three times the vertical angle. Find the measures of all the angles of the triangle?

14. The base angle of an isosceles triangle is 27° more than its vertical angle. Find all the angles of the triangle?

15. The vertical angle of an isosceles triangle is 30° more than its base angle. Find the measures of all the angles of the triangle?​

Answer 1

Answer:

15.(180-30)÷2=75 is the base angles

Answer 2

Answer:

12) angles are 50° & 40°

13)angles are 180/7° ,540/7° and 540/7°

14) angles are 42°,69°,69°

15) angles are 80°,50°,50°

Step-by-step explanation:

Remember the two base angles are same in isosceles triangle.

12)

let other angles be 5x° and 4x°

5x°+4x°+90°=180°

9x=180°-90°

9x=90°

x=10°

5x=50°

4x=40°

13)

let the vertical angle be x

then base angles = 3x & 3x

x+3x+3x=180°

7x=180°

x=180°/7 3x=540°/7

14)

let the vertical angle be x

base angle becomes x+27

x+x+27+x+27=180°

3x+54=180°

3x= 126

x=42°

x+27= 42+27=69

15)

let the base angles be x

vertical angle becomes x+30

x+x+x+30=180°

3x+30=180°

3x=150°

x=50°

x+30=80°