13-4x=1-x
13=4x+x=1-x+x
13-3x=1
13-1-3x=1-1
12-3x=0
12=3x
12/3=3x/3
4=x
Therefore, x=4
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
Answer:
y=125x+75
Step-by-step explanation:
Y= 125x+B
700=125(5)+B
700=625+B
700-625=625-625+B
75=B
Answer:
A - (4, –1.5)
Step-by-step explanation: Hope it helps :D