Answer:
6am
Step-by-step explanation:
He subtracted the 29fron the 30
----------------------------------------------------------------
Method 1
----------------------------------------------------------------
Since the numerators are the same, the smaller the denominators, the greater the fraction is.
Arranging from the least to the greatest

----------------------------------------------------------------
Method 2
----------------------------------------------------------------
Lets change all to the same denominators



Now that all the denominators are the same, we can arrange the fractions by comparing the numerators. The bigger the numerators, the greater the fraction.
Arranging from the least to the greatest
The larger number is (-7+14)/2 = 3.5.
The smaller number is (-7-14)/2 = -10.5.
_____
The two equations a+b=-7, a-b=14 can be solved to get these results. It is genrally convenient to solve them by adding one to the other, or subtracting one from the other.
Three planes a distinct lines have in common