For this case we have that by definition, the slope of a line is given by:
[tex]m = \frac {y_ {2} -y_ {1}} {x_ {2} -x_ {1}}[/tex]
We have as data that:
[tex]m = -2\\(x_ {1}, y_ {1}) :( 3,5)\\(x_ {2}, y_ {2}) :( 4, y)[/tex]
Substituting we have:
[tex]-2 = \frac {y-5} {4-3}\\-2 = \frac {y-5} {1}\\-2 = y-5\\-2 + 5 = y\\y = 3[/tex]
Finally, the value of y is 3.
Answer:
[tex]y = 3[/tex]
