Find the condition that the straight line `cx-by+b^2=0` may touch the circle `x^2+y^2=ax+ by`.

Show that the straight line 3x + 4y = 20 touches the circle x ^2 + y ^2 = 16.

Find the condition that the straight line y = mx + c touches the hyperbola x^(2) - y^(2) = a^(2) .

Find the condition that the straight line y = mx + c touches the hyperbola x^(2) - y^(2) = a^(2) .

Find the conditions that the line (i) y = mx + c may touch the circle x^(2) +y^(2) = a^(2) , (ii) y = mx + c may touch the circle x^(2) + y^(2) + 2gx + 2fy + c = 0 .

Find the condition that the straight line x cos theta+ y sin theta =p may touch the parabola y^(2)= 4ax .

Find the condition that the straight line lx+my=n touches the ellipse (x^(2))/(a^(2))+(y^(2))/(b^(2))=1

Find the condition, that the line lx + my + n = 0 may be a tangent to the circle (x - h)^(2) + (y - k)^(2) = r^(2) .

Find the condition that the line x cos alpha+y sin alpha=p touches the parabola y^(2)=4ax

Find the differential equation of all straight lines touching the circle x^2+y^2=a^2

Find the differential equation of all straight lines touching the circle x^2+y^2=a^2