We have, equation of ellipse is ‌3x2+8y2=K ‌⇒‌‌‌
x2
K
3
+‌
y2
K
8
=1 Here, a2=‌
K
3
and b2=‌
K
8
Equation of normal =4x−3y−5=0 Or y=‌
4
3
x−‌
5
3
Here, m=‌
4
3
and ‌
(a2−b2)m
√a2+b2m2
‌=‌
5
3
‌
(
K
3
−
K
8
)×
4
3
√‌
K
3
+‌
K
8
×‌
16
9
‌=‌
5
3
K2‌=20K K‌=20‌‌[∵K≠0] Since, (−2,m) lies cilipse ∵3(4)+8m2=20⇒m=±1 Equation of tangent of ellipse at ( −2,1 ) is −6x+8y=20⇒3x−4y+10=0