Difference between revisions of "2008 UNCO Math Contest II Problems/Problem 8"

(Created page with "== Problem == Triangle <math>ABC</math> has integer side lengths. One side is twice the length of a second side. <asy> draw((0,0)--(185/16,sqrt(225-(185/16)^2))--(40,0)--cycle...")
 
(Solution)
 
Line 22: Line 22:
  
 
== Solution ==
 
== Solution ==
 
+
a) 157
 +
b) 4n - 3
 +
c) 116
 +
d) Given that triangle ABC has integer side lengths and that one side is <math>a</math> times as long as the second, the maximum perimeter given third side, n, is <cmath>(a + 1)(\lfloor\frac{n}{a-1}\rfloor - 1) + n</cmath>
  
 
== See Also ==
 
== See Also ==

Latest revision as of 17:37, 23 November 2016

Problem

Triangle $ABC$ has integer side lengths. One side is twice the length of a second side.

[asy] draw((0,0)--(185/16,sqrt(225-(185/16)^2))--(40,0)--cycle,black); MP("A",(0,0),W);MP("C",(185/16,sqrt(225-(185/16)^2)),N);MP("B",(40,0),E); [/asy]

(a) If the third side has length $40$ what is the greatest possible perimeter?

(b) If the third side has length $n$ what is the greatest possible perimeter?

(c) Now suppose one side is three times the length of a second side and the third side has length of $40$. What is the maximum perimeter?

(d) Generalize


Solution

a) 157 b) 4n - 3 c) 116 d) Given that triangle ABC has integer side lengths and that one side is $a$ times as long as the second, the maximum perimeter given third side, n, is \[(a + 1)(\lfloor\frac{n}{a-1}\rfloor - 1) + n\]

See Also

2008 UNCO Math Contest II (ProblemsAnswer KeyResources)
Preceded by
Problem 7
Followed by
Problem 9
1 2 3 4 5 6 7 8 9 10
All UNCO Math Contest Problems and Solutions