Yes you got the correct answer.
#13:
s² = 144
√(s²) = √144
|s| = 12
s = -12 OR s = 12
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#15 (not sure what letter you used so I went with 'g')
(g-6)² = 25
√[(g-6)²] = √25
|g-6| = 5
g - 6 = -5 OR g - 6 = 5
g = 1 OR g = 11
I think it’s 24 I could be wrong but I’m pretty sure
Answer:

Step-by-step explanation:
We are given that Ben has a cell phone plan that provides 200 free minutes each month for a flat rate of $39.
We are also told that For any minutes over 200, Ben is charged $0.35 per minute.
let x be the minutes used each month
So, if 
So, coat will be $39
If 
So, Ben is charged $0.35 per minute
So, when 
So, charge = 
So, the piecewise functions accurately represents charges based on Ben's cell phone :

Answer:
7.2111(4 decimal places)
Step-by-step explanation:
a squared by b squared=c squared
36 + 16 is 52, so then you need to square root 52 which is 7.2111 to 4 decimal places. I hope you benefit from this. Cheers