Show that if a,b does not equal 0, then the line with x-intercept x=a and y-intercept y=b has the equation:
x/a + y/b = 1
x intercept: when y is zero
x/a + 0=1, or x=a
y intercept: when x is zero
0+y/b=1, or y=b
x/a + y/b = 1
x/a + 0=1, or x=a
y intercept: when x is zero
0+y/b=1, or y=b