Answer:
3
Step-by-step explanation:
A.
7 times number of cats=pay
if pay=49 then
7 times number of cats=49
divide both sides by 7
number of cats=7
da equaton can be
c=number of cats
7c=49
he fed 7 cats
B.
7c=49
divide both sides by 7
equality property of division
(7c)/7=49/7
math fact
(7/7)c=7
1c=7
identity property of division
c=7
identity property of multiplication
7 cats
C. 7 cats
B. (k+10f)(k-5f) you can tell in 2 ways. 1. if the second sign is neg then the signs in the factors are going to be one neg and one positive so that knocks out C and D. Then you look at the second term and since the 5 is positive then the 10 has to be positive so you end up with a positive 5kf.
The second way is to FOIL them out. When you check B you get

combine your like terms and you have your original expression of

Hope that helps
Factor out like terms
-y(7+y)=0