Write an equation of the line in general form:
Point on line: (1,2)
x-intercept: (a,0)
y-intercept: (0,a)
(a =/ 0)

that's algebra one, i think
grade 6 or 7th

use this point slope form formula

http://www.purplemath.com/modules/strtlneq2.htm



or
just y=mx+b
slope is (y2-y1)/(x2-x1)


ask if you need clarification

This post was edited by saber_x3 on May 18 2014 02:31pm

Here's the answer so you can check



a-0/0-a = -1 = m (slope)

so: y=-1x+b

plug in your point (1,2) : 2 = -1(1) +b -> 3 = b

equation of line: y = -1x+3