SOLUTION: Solve for x, assuming a, b and c are negative constants. (a) ax + b < c (b) (ax +b)/c < or = b

Algebra ->  Inequalities -> SOLUTION: Solve for x, assuming a, b and c are negative constants. (a) ax + b < c (b) (ax +b)/c < or = b      Log On


   



Question 1203082: Solve for x, assuming a, b and c are negative constants.
(a) ax + b < c
(b) (ax +b)/c < or = b

Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
.
Solve for x, assuming a, b and c are negative constants.
(a) ax + b < c
(b) (ax +b)/c <= b
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(a)     Step by step


    Starting inequality to solve is 

        ax + b < c.


    Subtract "b" from both side.  You will get

        ax < c - b.


    Divide both sides by "a".  Since "a" is negative (given), change the sign 
    of the inequality to the opposite one.  You will get

        x > %28c-b%29%2Fa.    ANSWER



(b)       Step by step 


     Starting inequality is 

         %28ax+%2Bb%29%2Fc <= b.


     Multiply both sides by "c".  Since "c" is negative number, change the sign of the inequality 
     to the opposite one.  You will get

          ax + b >= bc.


     Next, subtract "b" from both sides of the last inequality.  You will get

          ax >= bc - b.


     Now divide both sides by "a".  Since "a" is negative number, change the sign of the inequality 
     to the opposite one.  You will get

          x <= %28bc-b%29%2Fa = b%2A%28c-1%29%2Fa%29.


     Answer.  x <= %28bc-b%29%2Fa,  or, equivalently, x <= b%2A%28c-1%29%2Fa%29.

Solved in full,  with explanations.

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In writing Math, do not use this mixed combination of words and symbols " < or = ",
as it was in your post originally (before I fixed it).

Instead, use the symbol " <= ".