Answer:
Sierra=2songs
Matt=7songs
Yun SIl=14songs
step-by-step explanation:
Step 1
Let,The number of songs YunSil added = x
Number of songs Matt added = y
And number of songs Sierra added = z
Such that Matt has 5more than Sierra =y = 5 +z
Yun SIl has 2 times more thann Matt, x = 2y
x =2(5+z)=10 +2z
Step 2
The expression used to determine number of songs on each player given that the total of songs added on the three players =15 +z^3
Such that
YunSil+Matt+Sierra==15 +z^3
10+2z+ 5+z +z = 15 +z^3
4z +15 = 15 +z^3
4z=15-15+z^3
4z=+z^3
4=z^3/z
4=z^2
Z=√4 =2
Therefore Sierra has z=2songs
Matt has 5+z=5+2=7songs
YunSil has 2(5+z)= 2x7=14songs