The general line through (a,b) and (c,d) is
[tex](c-a)(y-b)=(d-b)(x-a)[/tex]
Can you see why this is a line through both points?
In our case, we have points (-1,2) and (3,10)
[tex](3 - -1)(y - 2) = (10 - 2)(x - -1)[/tex]
[tex]4y -8 = 8x + 8[/tex]
[tex]y = 2x + 4[/tex]
Check: 2(-1)+4=2 good, 2(3)+4=10 good
Answer: y=2x+4
