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solve. 4+3x<28

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torito101 | Student, Grade 9 | eNotes Newbie

Posted May 18, 2010 at 3:07 AM via web

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solve.

4+3x<28

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pohnpei397 | College Teacher | (Level 3) Distinguished Educator

Posted May 18, 2010 at 3:19 AM (Answer #1)

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You do this problem just the same way that you would do it if it were not an inequality.  What that means is that you need to get the x term on one side by itself and then simplify it down to where it is just x (instead of 3x).

So, what you do first is to subtract 4 from both sides.  Then you get

3x < 24

So then you divide both sides by 3 and you get

x < 8

And that is your answer.  Plug in a number to check and see if it's right.  We'll choose 7.

4 + 3*7 < 28

4 + 21 < 28

25 < 28

True.  So numbers less than 8 make the inequality true.

Now we'll try a number bigger than 8.

4 + (3*9) < 28

4 + 27 < 28

Not true.  So numbers bigger than 8 make the statement false.

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neela | High School Teacher | Valedictorian

Posted May 18, 2010 at 3:31 AM (Answer #2)

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To solve 4+3x<28.

Solution:

4+3x < 28.  If we add equals or subtract equals the inequality remains. So we subtract 4 from both sides so that x's reains on one side and numbers moves to the other side.

4+3x -4< 28 -4. Or

3x < 24. If we divide by positive equals (or multiply by positive equals) both sides, the inequality does not change.

3x/3 <

x < 24/3. Or

x < 8

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hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted May 18, 2010 at 5:35 AM (Answer #3)

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4+3x <28

in order to sove the problem, we need to to find X values , so we need to keep X in one side by itself by using subtraction and division.

first you subtract 4 from both sides:

4+3x - 4 < 28-4

3x < 24

Now you divide by 3 ...

3x/3 < 24/3

==> x < 8

what does that mean?

it means that x values are any real number less that 8 

which we could perform by the interval (- inf, 8)

then, x = (- inf, 8)

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shihan | Student, Undergraduate | Salutatorian

Posted October 17, 2011 at 11:57 AM (Answer #4)

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4+3x -4< 28 -4. Or 3x < 24. If we divide by positive equals (or multiply by positive equals) both sides, the inequalitydoes not change. 3x/3 < x < 24/3. Or x < 8

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Wiggin42 | Student, Grade 11 | Valedictorian

Posted March 23, 2014 at 5:34 PM (Answer #5)

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4+3x<28

Undo addition first

3x < 24

Undo multiplication next

x < 8

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atyourservice | Student, Grade 10 | Valedictorian

Posted April 19, 2014 at 10:11 PM (Answer #6)

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4+3x<28

minus 4 on both sides, this cancels out the 4

3x < 24

now divide by x

(3x)/3 < 24/3

x < 8

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zumba96 | Student, Grade 11 | Valedictorian

Posted May 9, 2014 at 11:47 PM (Answer #7)

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4+3x<28

Do this the way you would do a normal equation. Move the terms on one side

3x<28-4

3x<24

24 is divisible by 3 therefore

`(3x)/3` < `24/3`

x<8

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acompanioninthetardis | Student, Undergraduate | Valedictorian

Posted May 18, 2014 at 4:26 PM (Answer #8)

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4+3x<28

3x<28-4

3x<24

x<8

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nisarg | Student, Kindergarten | Valedictorian

Posted June 19, 2014 at 2:59 AM (Answer #9)

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4+3x<28

3x<24

x<8

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jess1999 | Student, Grade 9 | Valedictorian

Posted June 20, 2014 at 2:49 AM (Answer #10)

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4 + 3x < 28

To solve this equation you can basically think of " < " as " = "

First subtract 4 from both sides making your equation

3x < 24 now divide both sides by 3

Dividing both sides by 3 would make your equation

x < 8 which is your answer

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nisarg | Student, Kindergarten | Valedictorian

Posted June 20, 2014 at 4:29 PM (Answer #11)

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4+3x<28

3x<24             subtract 4

x<8                   divide by 3

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ik9744 | TA , Grade 9 | Valedictorian

Posted June 26, 2014 at 6:17 AM (Answer #12)

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4+3x<28 Equation

3x < 28-4 Subtract 4 on both sides

3x < 24 Divide 3 on both sides

x < 8 Answer 

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givingiswinning | Student, Grade 10 | Valedictorian

Posted August 16, 2014 at 1:24 AM (Answer #13)

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4+3x<28

3x < 24

divide by x

(3x)/3 < 24/3

x < 8

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