the sum of the lengths of any two sides of a triangle is greater than the length of the third side. if you take the three sides of a triangle and add them in pairs, the sum is greater than (not equal to) the third side. if that is not true, then it is not possible to construct a triangle with the given side lengths.
68 adults and 51 students attended the play.
Let x = Number of adults
y= Number of students
As per given,
Put (ii) in (i) , we get
So, (from (ii))
Hence, 68 adults and 51 students attended the play.