We have,
Equation of ellipse is x24+y23=1
On comparing that,
x2a2+y2b2=1
a2=4,b2=3
Equation of line
y+2x=4
y=−2x+4
On comparing that,
y=mx+c
So,
Slope of this line m=−2
Now equation of a tangent having slope m=-2 is
y=−2x+√4×4+3
y=−2x+√19
Hence, this is the
answer.