Find equation of the line passing through the point (2, 2) and cutting off intercepts on the axes whose sum is 9.

Explanation

`x/a + y/b = 1`

given `a+b=9`

`b=9-a`

so `x/a + y/(9-a) = 1`

`2/a + 2/(9-a) = 1`

`2(9-a) + 2a = a(9-a)`

`18- 2a + 2a = 9a - a^2`

`a^2 - 9a + 18=0`

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