Question

find the area of the triangle whose vertices are (a,b+c),(a,bc) and (a,c).

Answer 1

formula- 1/2 [x1(y2-y3) +x2(y3-y1) +x3(y1- y2)]

1/2[ a(bc-c) + a(c- (b+c)) + a(b+c-bc)]

1/2[ac(b-1)+ a(c-b-c) + a(b{1-c}+c)]

1/2[acb - ac -ab + ab{1-c} + ac]

1/2[acb -ac -ab + ab -abc +ac]

1/2×0

=0