15. 
Add "g" on both sides
Multiply 5 on both sides to get x by itself
x = 5(a + g)
x = 5a + 5g
18. a = 3n + 1
Subtract 1 on both sides
a - 1 = 3n
Divide 3 on both sides to get n by itself
= n
21. M = T - R
Add "R" on both sides to get "T" by itself
M + R = T
24. 5p + 9c = p
Subtract "5p" on both sides
9c = p - 5p
9c = -4p
Divide 9 on both sides to get "c" by itself
c = 
or c = 
27. 4y + 3x = 5
Subtract "4y" on both sides
3x = 5 - 4y
Divide 3 on both sides to get "x" by itself
x = 
x = 
For each deposit she makes 3.5 is being subtracted for the money she makes so 8000 would be 45 tries
Since the time to failure distribution is
exponential, the distribution is F (n) = 1 – e ^ (-x/48)
The probability of failure between months 60
and 72 is the same as the probability that the battery will fail in 12 months,
since the exponential distribution is memoryless F (12) = 0.221
<span> </span>
Y = 1/6x + 4....the slope here is 1/6. A perpendicular line will have a negative reciprocal slope. All that means is " flip " the slope and change the sign.
So the slope of a perpendicular line will be -6/1 or just -6...see how I flipped the slope and changed the sign.
