Step-by-step explanation:
The answer of the question number 1 is b
The answer of the question number 2 is also c
The answer of the question number 3 is b
The answer of the question number 4 is a
D) is the answer i already done that question
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
The two lines are perpendicular because both of the lines intersects
Answer: hello!
<h3>The expression is not factorable with rational numbers.
</h3><h3>5−21x</h3>