Question

Show that points A(a,0), B(0,a)and C(1,1)are collinear if 1/a+1/b=1.​

Answer 1

Answer:

Use area of triangle form by these three points is equal to zero

area of t triangle=1/2 {a (b-1)+0+1 (0-b)}

0=ab-a-b

a+b=ab

divide both side by ab

a/ab+b/ab=ab/ab

1/b+1/a=1

hence

1/a+1/b=1

Answer 2

Refer to the attachment ☺️