Let x tickets sold be adults, then (1024-x) were of childrens tickets, 9x+(1024-x)4 = 7680. The above equation is for total money solve it you will get x=720 hence, number of adult tickets were 720 and number of child tickets were 300 :)
If it has 3 sides then it's a triangle.
Using the formula
where
![s= \frac{a+b+c}{2}](https://tex.z-dn.net/?f=s%3D%20%5Cfrac%7Ba%2Bb%2Bc%7D%7B2%7D%20)
and a=5 b=5 c=8
∴
5 1/2 * 2 1/3 =
11/2 * 7/3 =
77/6 =
12 5/6 <===