Answer:
125.141
Step-by-step explanation:
Assuming that this is an equilateral triangle, I am going to divide this triangle in half to get a right triangle.
17 is our hypotenuse
17/2 = 8.5, this is one of our legs
The other leg is our height, which we will find.
We use Pythagoras Theorem to find the height/leg: 
= 14.72243186
Now, we use another formula to find the area of the triangle: 
14.72243186 × 17 = 250.2813416
250.2813416 ÷ 2 = <u>125.1406708</u>
Answer:
Step-by-step explanation:
They are all true
The length of each leg is 6
I would use the pythagorean theorem to find the lengths of each side. a² + b² = c².
Side AB is one we're looking for. If you make other right triangle with that same side you can see that one length is 4 and the other is 3. So, 4² + 3² = c² → 25 = c² → 5 = c. Side AB is length 5.
Side AC is another. Do the same with that side and you get that one length is 4 and the other is 3. (This is the same one as above) so side AC is length 5.
Side BC is the last one. One of the lengths is 1 and the other is 1 → 1² + 1² = c² → 2 = c² → 1.414213562 = c so side BC is approximately length 1.41.
Add each length up and you get a perimeter of roughly 11.4
