The LCD (least common denominator) is the lowest number that both denominators (12 and 5) go into. The lowest number that both 5 and 12 go into is 60. The LCD of the two fractions is 60.
Answer:
parallel:

perpendicular:

Step-by-step explanation:
original line:
-7x + 8y = 4
m = 7/8
parallel:
m = 7/8
L: 7x - 8y = k
(4, -4) -> L
28 + 32 = 60 = k
L: 7x - 8y = 60
perpendicular:
m = -8/7
L: -8x + 7y = k
(4, -4) -> L
-32 + 28 = -4 = k
L: -8x -7y = -4
=> 8x + 7y = 4
Answer:
41 degrees
Step-by-step explanation:
The three angles need to add up to 180 degrees!
I'm not sure what side is missing but you could use the proportions
A/B=X/Y or B/C=Y/Z or CA/=ZX. it also works if you reverse this for example B/A=Y/X