Find the lowest common multiple by stating out the multiples of 14 and 21. Like this:
14,28,42,56,70,84,98,112,126...
21,42,63,84...
There you have it. 84 is the lowest common multiple.
I HOPE THIS HELPS :) IM SORRY IF IM WRONG
Answer: i think A
Step-by-step explanation:
Answer:

Note:
Three-tenths reapeating is 
2x²-3x-15=5
2x²-3x-15-5=0
2x²-3x-20=0
½(2x+5)(2x-8)
-2x=-5
x=-5/2
2x-8=0
2x=8
x=4
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