Question

determine o perimetro e a area do triangulo cujo vertices abc A(-3,1) B (1,4) C (2-2)

Answer 1

determinante:
-3...1...1
1....4....1
2...-2....1
D = -12-2+2-8-8+6
D = -22
A = |D|
A = 22
perímetro:
AB² = [1-(-3)]² + (4-1)² = 4² + 3² = 25
AC² = [2-(-3)]² + (-2-1)² = 25 +9 = 34
BC² = (2-1)²+(-2-4)² = 1 + 36 = 37
perímetro = 25+34+37 = 59+37 = 96