In general the equation through (a,b) and (c,d) is
[tex](y-b)(c-a)=(x-a)(d-b)[/tex]
Can you see that this is a line and that both (a,b) and (c,d) are on it?
Here we're given (a,b)=(-6,-5) and (c,d)=(-4,-4)
[tex](y- -5)(-4 - -6) = (x - -6)(-4 - 5)[/tex]
[tex]2(y+5)=x+6[/tex]
[tex]2y + 10 = x + 6[/tex]
[tex]x - 2y = 4[/tex]
[tex] y = \frac 1 2 x - 2 [/tex]
Either of the last two are fine answers.
