Question

p.t te points (-7,-3),(5,10),(15,8)&(3,-5) taken in order are the corners of a parallelogram.and find its area.

Answer 1

Let A(-7,-3), B(5,10), C(15,8), D(3,-5) be the corners of the parallelogram.
Use the formula for area of a triangle with co-ordinates of its vertices being (x1,y1), (x2,y2), (x3,y3) =
absolute value of (1/2)[x1(y2 - y3) + x2(y3 - y1) + x3(y1 - y2)]
 
Area of parallelogram  = 2 x Area of triangle ABC=absolute value of  
2 x (1/2) x [(-7)(10 - 8) + 5{8 - (-3)} + 15{(-3) - 10}]
 = absolute value of ( -14 + 55 - 195) = 154 sq units