Triangle ABC has altitudes AD, BE, and CF. If AD=14, BE=16, and CF is a positive integer, then find the largest possible value of CF.
Ive tried drawing things out but don't know how to figure it out. If anyone can help that would be great.
Given that triangle ABC has altitudes AD=14, BE=16, and CF=h, where h is a positive integer, we need to find the largest possible value of h.
### Step 1: Use the area formula with altitudes
The area of triangle ABC can be expressed in terms of the altitudes and the corresponding sides:
Area=12×a×ha=12×b×hb=12×c×hc
where ha=AD, hb=BE, and hc=CF=h, and a, b, and c are the lengths of the sides opposite the vertices A, B, and C, respectively.
### Step 2: Express the sides in terms of the area and altitudes
Let the area of triangle ABC be denoted as K. Then:
K=12×a×14=7a
K=12×b×16=8b
K=12×c×h=12ch
### Step 3: Equate the expressions for the area K
From the first two equations:
7a=8b⇒a=8b7
Using the equation for K involving h:
7a=12ch
Substitute a=8b7 into the equation:
7(8b7)=12ch
Simplify:
8b=12ch
Multiply both sides by 2:
16b=ch
Thus:
h=16bc
### Step 4: Maximize h
We aim to maximize h=16bc, where b and c are positive integers.
Recall that K=7a=8b=12ch. We want to maximize h, so:
c=16bh
To maximize h, minimize c. Since b=7, a=8, choose b=7 and c=1 which gives:
h=16×71=112
However, since b=gcd(7,8), choose b=7 for simplicity. So:
\[
K = 112, h = 1
]
Thus:
h≤112
### Final Answer:
Since h=112, the maximum value for the given maximum number is 112.