help plz asap . .... .............

Answer:
[tex]\large\boxed{-\dfrac{5}{3}}[/tex]
Step-by-step explanation:
Parallel lines have the same slope.
We have the equation of a line in a standard form:
[tex]5x+3y=15[/tex]
Convert to the slopie-intercept form:
[tex]y=mx+b[/tex]
[tex]5x+3y=15[/tex] subtract 5x from both sides
[tex]3y=-5x+15[/tex] divide both sides by 3
[tex]y=-\dfrac{5}{3}x+5\to m=-\dfrac{5}{3}[/tex]