Question

(7) (4,2) (3.9) and (10,10) are three verities of Triangle. Than Area of triangle is? ​

Answer 1

△ABC has vertices A(4,2),B(3,9) and C(10,10).

The area of a triangle formed by joining the points (x1,y1),(x2,y2),(x3,y3) is

$\frac{1}{2} |x1(y2 - y3) + x2(y3 - y1) +x3(y1 - y2) |$

∴ Area of △ABC

$= \frac{1}{2} |4(9 - 10) +3(10 - 2) + 10(2 - 9) \\ = \frac{1}{2} | - 4 + 24 - 70| \\ = \frac{50}{2}=25$

Hence, area of triangle ABC is 25.