For this case we have to by definition, given two points through which a line passes:
[tex](x_ {1}, y_ {1})[/tex] and [tex](x_ {2}, y_ {2})[/tex]
We can find the slope using the following formula:
[tex]m = \frac {y_ {2} -y_ {1}} {x_ {2} -x_ {1}}[/tex]
In this case we have the slope and we must find the "y" coordinate of one of the points.
We have:
[tex](x_ {1}, y_ {1}): (3,4)\\(x_ {2}, y_ {2}) :( 10, y)\\m = - \frac {2} {7}[/tex]
Substituting we have:
[tex]m = \frac {y_ {2} -4} {10-3} = \frac {y-4} {7}[/tex]
So:
[tex]- \frac {2} {7} = \frac {y-4} {7}\\\frac {-2} {7} = \frac {y-4} {7}[/tex]
Thus:
[tex]y_ {2} -4 = -2\\y_ {2} = - 2 + 4\\y_ {2} = 2[/tex]
Thus, the "y" coordinate of point 2 is: 2
Answer:
[tex]y_ {2} = 2[/tex]