SOLUTION: if an isosceles triangle has a perimeter of 24 units, what is a possible set of lengths of all three sides

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Question 866372: if an isosceles triangle has a perimeter of 24 units, what is a possible set of lengths of all three sides
Found 2 solutions by ewatrrr, MathLover1:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
if an isosceles triangle has a perimeter of 24 units,
what is a possible set of lengths of all three sides: 10, 10 , 4

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
Let's determine first what the largest possible measure each of
the two congruent legs can have:
The smallest the base can be is 1, so the two congruent legs
would have length %2824-1%29%2F2 or maximum 11 each if the length an integer
Now we will determine what the smallest possible measure each of
the two congruent legs can have:
If the two legs are "a" units each and the base is c, then by the
triangle inequality:
(1) +2a+%3E+c

and since the perimeter P+=+24+=+a+%2B+a+%2B+c,
2a+%2B+c+=+24
(2) c+=+24+-+2a
Substitute the 24+-+2a for c in equation (1)
2a+%3E+c
2a+%3E+24+-+2a
4a+%3E+24
a+%3E+=24%2F4
a+%3E+6
Therefore the smallest "a" can be is 7 to 11: 7,8,9,10, and 11.
and, since c=24-2a, "c" can range from 24-+2%2A11=24-22=2 to 24-+2%2A7=24-14=10: "c" can be 2,4,6,8, and 10.
So there are 5 possible triangles. Here they all are:

1. sides 7, 7, 10
2. sides 8, 8,8
3. sides 9, 9, 6
4. sides 10, 10, 4
5. sides 11, 11, 2