Answer:
6:120
7:100
10:40 50 90
Explanation:
6:sum of internal angle of triangle is equal to exterior angle
7:10^2=100
10:let angle be x then
4x+5x+9x=180(sum of all side of triangle)
or,18x=180
..x=10
hence, 4x=40,5x=50,9x=90
11:
as we know
side of equilateral triangle is 30
now <c is 30 degree
so, ,c+<e+<f=180 degree
hence , its prooved that CDE is equtrilateral triangle