Notice that x+4 is one of the denominators, and that x(x+4) is the LCD.
x
Thus, mult. ------- by x(x+4), obtaining x^2.
x+4
Next, mult. [ 1/x + 1/(x+4) by x(x+4), obtaining x+4 + x = 2x+4 or 2(x+4)
x^2
Then the simplified fraction becomes ----------
2(x+4)
Generally Brainly allows you to post only 1 or 2 questions at a time. I will do #15 as a courtesy to you, but want you to try #16 yourself (or to post it separately).
-4, 2, 8, 14, ... is an arithm. seq. Every new term is equal to the previous term, plus 6: -4+6 = 2; 2+6=8, and so on. Thus: first term is a = -4; common difference is d = 6
a(50) = a(1) + (50-1)(6), or a(50) = -4 + (49)(6) = 290 (answer)
Answer:
and 
Step-by-step explanation:
The equation of the isotope decay is:

14-Carbon has a half-life of 5568 years, the time constant of the isotope is:


The decay time is:
(There is no a year 0 in chronology).

Lastly, the relative amount is estimated by direct substitution:





This is just about similar triangle
mn=2jl=22
mo=2lk=26
jk=2on=40
P80 = 36 * 0.80 = 28.8
The above equation shows that the 80th percentile will have 28.8 values below it. So obtaining the 29th value will be the 80th percentile.
Looking at the given values, P80 = 67.