Find the equation of the straight line which passes through the point (1, – 2) and cuts off equal intercepts from axes.

The equation of line in intercept form is:

where a and b are the intercepts on the axis.

Given that: a = b

⇒ x + y = a …(i)

If eq. (i) passes through the point (1, - 2), we get

1 + (-2) = a

⇒ 1 – 2 = a

⇒ a = -1

Putting the value of ‘a’ in eq. (i), we get

x + y = -1

⇒ x + y + 1 = 0

Hence, the equation of straight line is x + y + 1 = 0 which passes through the point (1, – 2).