Answer:
I believe you have to add 15.9 on both sides
-4z+1 = bz+c
Take all z's to one side
1 = bz+c+4z
Then take c to the other side
1-c = bz+4z
Factor out z on the right side
1-c = z(b+4)
Then divide (b+4) from both sides
z = 1-c/b+4 or (1-c)/(b+4)
Given a quadratic equation

the quadratic formula states that the solutions are

Plug your values to get

Which evaluates to

So, the two solutions are

To solve for s you'll have to subtract 5 on both sides.
-3 > s + 5
-3 - 5 > s
-8 > s
Hope this helps :)
128/100=32/25
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