Question

T
3
If the points (1, 2) and (3, 4) were to be on the opposite side of the line
(a) 7<a< 11
(b) a = 7
the opposite side of the line 3x - 5y + a =0, then
(c) a = 11
(d) a< 7 or​

Answer 1

Answer:

If the points lie on opposite sides of the line then L11/L22<0

(3-10+a)/(9-20+a)<0

a-7/a-11<0

(a-7)(a-11)<0

Therefore a<7ora>11

Answer 2

Answer:

let p(1,2) and q(3,4)

( x1,y1) (x2,y2)

if the points were to be opposite side of the line then

L11/L22<0

L11=3(1)-5(2)+a=a-7

L22=3(3)-5(4)+a=a-11

(a-7)/(a-11)<0

therefore

7<a<11

and the above ans is wrong