y intercept of -5x-4y=10

Answer 1

in the form y = mx + b,
b is the y-intercept, so ...

-5x-4y=10
-4y = 5x + 10

I will leave the last step for you

Answer 2

-5x--4y = 10
Y-int. = C/B = 10/-4 = -2.5.