I have two word problems that I do not know what to do. can some please explain how to I solve this.

---------------------------------------------------The illumination at a point is inversely proportional to the square of the distance of the point from the light source and directly proportional to the intensity of the light source. If two light sources aresfeet apart and their intensities areIandJrespectively, at what point between them will the sum of their illuminations be a minimum? Instruction: Give your answer in terms ofs,IandJ.

Solution:

Letxbe the distance fromIat which the sum of the illuminations be minimum. Then

x= ______

Find the equation of the line that is tangent to the ellipse in the first quadrant and forms with the coordinate axes the triangle with smallest possible area (aandbare positive constants.)

The equation of the required line is:

____x + ____y + ______ = 0