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Question:

lilbree217x
lilbree217x
Student
High School - 9th Grade

Please solve -4-5v<-29.

step by step

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Posted by lilbree217x on Sunday February 22, 2009 at 3:27 PM and tagged with algebra, equasions, inequalities, math.

Answers:


  1. ladyvols1 Teacher
    High School - 9th Grade

    eNotes Editor

    To solve this inequality you must first isolate the variable.  To do this you must add +4 to each side.  After this is done you will be left with -5v<-25.  The next step will be to divide each side by -5.    -5/-5v < -25/-5.  Following this step you will have your answer.  V< 5.

    Thus, negative 4 plus a negative 5V is any number less than a negative 25.  Your solution is V is any number less than 5.

    Sources:
    http://www.aaamath.com/g725-inequalities.html
    http://www.enotes.com/sat-prep/sat-drills
    http://www.math.com/school/subject2/lessons/S2U3L4DP.html

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    Posted by ladyvols1 on Sunday February 22, 2009 at 6:44 PM


  2. kmieciakp Teacher
    High School - 12th Grade

    But when you multiply both sides of an inequality by a negative number, you reverse the inequality.  So the answer is v>5

    Note this example, if answer were v < 5 :

    suppose v=1;

    then -4 -(5x1)<-29

    -4 - 5 < -29

    -9 < -29--which is not true.

    But suppose v is a number greater than 5, like 6:

    -4 - (5x6) < -29

    -4 - (30) < -29

    -34 < -29.

    and just to be sure, let's make sure v cannot equal 5:

    -4 - (5-5) < -29

    -4 - (0) < -29

    -4 < -29--not true, so that's settled.

    To recap then, solve -4 - 5v < -29 like this:

    -4 - (5v) < -29

    -5v < -29 +4

    -5v < -25

    (-1/5)5v < -25(-1/5)

    when multiplying both sides of an inequality by a negative number, you need to flip the inequality

    v > 5

     

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    Posted by kmieciakp on Sunday February 22, 2009 at 9:26 PM


  3. lizbethortiz Student
    High School - 12th Grade

    -4-5v<-29      you first cancelled the -4 by adding +4 then you do the same to the other side by adding  4 to -29 = -25

    -5v<-29+4

    -5v<-25        Then you divide by -5 to both sides by you need to change the symbol because you are dividing a negative

    v>-25/-5

    v>5

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    Posted by lizbethortiz on Friday February 27, 2009 at 9:15 PM