The generic equation of the line is:
[tex]y-yo = m (x-xo) [/tex]
Where, the slope is given by:
[tex]m = \frac{y2-y1}{x2-x1} [/tex]
Substituting values we have:
[tex]m = \frac{5-1}{5-1} [/tex]
Rewriting:
[tex]m = \frac{4}{4} [/tex]
[tex]m = 1[/tex]
We now choose an ordered pair:
[tex](xo, yo) = (1,1) [/tex]
Then, replacing values we have:
[tex]y-1 = (x-1) [/tex]
Rewriting the equation we have:
[tex]y = x-1+1 y = x y - x = 0[/tex]
Answer:
the equation of the line that passes through the points (1,1) and (5,5) is:
A. Y-x=0
