I assume you mean Y-intercept?
well the linear equation were used to is Y= mx + b where m is the slope and b is the y-intercept. so first lets get it into this form.
3x + 5y = 9 we wanna get y by itself so we first subtract 3x from both sides
5y = 9 - 3x now we divide both sides by 5 we get
y = 9/5 - 3x/5 or y= -3x/5 + 9/5
Slope = m = -3/5
y-intercept = 9/5 or (0, 9/5)