Answered

Given the side lengths, determine whether the triangle is acute, right, obtuse, or not a triangle.
15, 16, 21
A Not a Triangle
B Acute
Obtuse
D Right

Answer :

sqdancefan

9514 1404 393

Answer:

  B  acute

Step-by-step explanation:

We can define a "form factor" for a triangle as ...

  f = a² +b² -c²

where c is the longest side length. It will be interpreted as follows:

  • negative -- obtuse triangle
  • zero -- right triangle
  • positive -- acute triangle

For this triangle, our "form factor" is ...

  f = 15² +16² -21² = 225 +256 -441 = 40 . . . . a positive number

The triangle is Acute.

${teks-lihat-gambar} sqdancefan

Other Questions