Question

Which property justifies this r(s + t) = rs + rt statement

Answer 1

R(s+t) = rs + rt represents Distributive Property because r is multiplying s and t
i.e. ( r*s + r*t ) 
    = rs + rt

So correct answer is Distributive Property.

hope this helps  :)

Answer 2

R(s+t)= rs + rt is represented by Distributive property . The answer is Distributive property Hope this helps