Please answer as quickly as possible!

If they are collinear, then the equation of line, from (a,0) and (0,b), in y = mx + c form, is,

y = (-b/a)x + a

and the third point must be on this line.

1 = -b/a + a

a = -b + a²

a + b = a²

Divide both sides by a²,

1/a + 1/b = 1

Regards,

Team,

TopperLearning.