Answer:
2
Step-by-step explanantion:
You sustitute 20 for s to get 20 = d + 18, subtract 18 from both sides and you get d = 2.
C) 6^15
When you simply the fraction you get 6^15 or 470184984576.
Let y be x, and x be y.
x = 4y - 8
Rearrange to make y the subject.
x + 8 = 4y
Therefore
y = (x + 8) / 4
is the inverse.
<h3>Substitute and Check:</h3>

<h3>We can stop here and conclude that ( 1 , 3 ) is not a solution to this system, since it does not even satisfy the first equation, but check for the other one just in case:</h3>
