Distributive Property:
The distributive property lets you multiply a sum by multiplying each addend separately and then add the products.
In numerical form we have:

Now let us use this property for our question:
(-2.5)(3-8y)
Here we have ,
a=(-2.5) , b=3 and c=-8y
So using distributive property here,

=-7.5 +20y
So answer is -7.5 +20y