Question

Triangle ABC is a right triangle on the coordinate system and its vertices are (−2, 5),

(−2, 1), and (1, 1). What is the area of triangle ABC?

Answer 1

name them

A=(-2,5)

B=(-2,1)

C=(1,1)

sides:

AB=c=4

AC=b=√(3²+4²)=5

BC=a=3

then we do this

2p=a+b+c

2p=3+4+5=12

p=6

then we calculate the area:

√(p(p-a)(p-b)(p-c))

Area=√6(6-3)(6-4)(6-5)

Area=√(6×3×2×1)

Area=√36=6