Triangle Problem - Is it possible to solve this?

[gmatz]

Is it possible to figure out the area of a triangle with sides of 4,8, and 11?

[givemeanid]

Is it possible to figure out the area of a triangle with sides of 4,8, and 11?

Sides = 4, 8 and 11. Lets call them x,y and z
Perimeter = 23
1/2 (Perimeter) = s = 11.5

Area = sqrt (s(s-x)(s-y)(s-z)) = sqrt[11.5 * (11.5 - 4) * (11.5 - 8 ) * (11.5 - 11)] = 12.29

[gmatz]

Thanks. Real quickly, what are these relationships called?

1) 1/2 (Perimeter) = s = 11.5

2) Area = sqrt (s(s-x)(s-y)(s-z)) = sqrt[11.5 * (11.5 - 4) * (11.5 - 8 ) * (11.5 - 11)] = 12.29

[givemeanid]

I do not recall the name of the formula. It's been a while since those math classes

If you have a triangle with sides x, y and z, then the area of the triangle is sqrt{s*(s-a)*(s-b)*(s-c)} where s is half the perimeter i.e s = (x+y+z)/2.

[gmatz]

thanks

[gmatz]

Just looked it up on the Internet. I'm curious to know where you reviewed this (in a class)? I've never come across this problem during my studies, but just thought of it thinking it could be a problem.