Answer:
doctorate salary:  d = $71,000
bachelor salary:     b = $55,000
Step-by-step explanation:
doctorate salary:  d
bachelor salary:     b
relationship between b and d:  d = 2b - $39,000
Unfortunately, your "1 + 126,000" could not be correct.  I'm going to assume that the total of the two salaries is $126,000.  If that's the case, then:
bachelor salary + (2 times bachelor salary less $39,000) = $126,000.  In symbols, 
b + 2b - $39,000 = $126,000
Consolidating the 'b' terms results in 3b - $39,000 = $126,000, and so:
3b = $126,000 + $39,000 = $165,000
Dividing both sides by 3 yields the bachelor salary:  b = $55,000
Then the doctoral salary is 2b - $39,000 = 2($55,000) - $39,000, or $71,000.
Check:  Does b + (2b - $39,000) = $126,000?  Yes.
Then the doctoral salary is d = $103,000, and the bachelor salary $29,000