Answer:
Step-by-step explanation:
For two lines to be parallel, they must have the same slope
Get the slope of each line
For L1;
m1 = -2-4/1-n
m1 = -6/1-n
For L2;
m2 = 5-3/1-4
m2 = 2/-3
m2 = -2/3
Since they have the same slope, m1 = m2
-6/1-n = -2/3
6/1-n = 2/3
Cross multiply
2(1-n) = 6(3)
2-2n = 18
-2n = 18 - 2
-2n = 16
n = -16/2
n = -8
Hence the value of n is -8
m-a = n
a=m-n
Subtract m from each side
a-m = m-n-m
a-m = -n
Multiply each side by -1
-a+m = n
Answer C
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