Answer:
[tex]15 < n < 25[/tex]
Step-by-step explanation:
Given
[tex]Side\ 1 = 20cm[/tex]
[tex]Side\ 2 = 5cm[/tex]
[tex]Side\ 3 = n[/tex]
Required
Determine n using inequality
The three sides of the triangle must satisfy two of the following conditions
[tex]Side\ 1 + Side\ 2 > Side\ 3[/tex]
[tex]Side\ 1 + Side\ 3 > Side\ 2[/tex]
[tex]Side\ 2 + Side\ 3 > Side\ 1[/tex]
Substitute values in the above inequalities;
[tex]20 + 5 > n[/tex]
[tex]20 + n > 5[/tex]
[tex]5 + n > 20[/tex]
Solve each of the inequalities
[tex]20 + 5 > n[/tex]
[tex]25 > n[/tex]
[tex]n < 25[/tex]
[tex]20 + n > 5[/tex]
[tex]n > 5 - 20[/tex]
[tex]n > -15[/tex]
[tex]5 + n > 20[/tex]
[tex]n > 20 -5[/tex]
[tex]n>15[/tex]
Since, the second inequality has negative, we simply ignore it
So, we combine the first and the third:
[tex]n>15[/tex] and [tex]n < 25[/tex]
[tex]15 < n[/tex] and [tex]n < 25[/tex]
Combine both
[tex]15 < n < 25[/tex]
The second question is not clear and it is unanswerable