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Tutors Answer Your Questions about Inequalities (FREE)
Question 571061: How do you solve -12x=72? Found 2 solutions by Alan3354, stanbon: Answer by Alan3354(21542) (Show Source): Answer by stanbon(48502) (Show Source):
Question 570274: Find the no. of integral solutions of:
xy=2x-y
i tried using the AM-GM inequality but i didnt get the solution to this.how should i start?
Answer by Edwin McCravy(6927) (Show Source):
You can put this solution on YOUR website!
xy = 2x - y
xy + y = 2x
y(x + 1) = 2x
y =
The graph of that has vertical asymptote x=-1 and horizontal asymptote y=2.
We plot that graph:
The only possibility of y having an integral value when x has an integral
value, is for integral values of x when y is at least 1 unit away from
its horizontal asymptote y=2, and that is when
1
By ordinary methods of college algebra, that has solution
[-3,-1)U(-1,1]
So we only need to try x-values in that region
which are -3, -2, 0, and 1
Substituting those in
y =
we find the only four integral solutions:
(-3,3),(-2,4),(0,0), (1,1).
So the number of integral solutions is 4.
Edwin
Question 569577: To pass a course, corrina needs an average score of 60 or more. If Corina 's scores are 66 72 90 49 and 59 find the minimum score that maria can get on her sixth and last exam and pass the sourse. Found 2 solutions by JBarnum, nerdybill: Answer by JBarnum(1826) (Show Source): Answer by nerdybill(5403) (Show Source):
You can put this solution on YOUR website!To pass a course, corrina needs an average score of 60 or more. If Corina 's scores are 66 72 90 49 and 59 find the minimum score that maria can get on her sixth and last exam and pass the sourse.
.
Let x = minimum score on sixth exam
then
(66+72+90+49+59+x)/6 = 60
(336+x)/6 = 60
336+x = 360
x = 24
Question 568715: -2r -7 is greater than or equal to -9 -r Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Add  to both sides.
 Add  to both sides.
 Combine like terms on the left side.
 Combine like terms on the right side.
 Divide both sides by  to isolate  . note: Remember, the inequality sign flips when we divide both sides by a negative number.
 Reduce.
----------------------------------------------------------------------
Answer:
So the solution is
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
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Question 568193: Solve the inequality and represent your answer in set builder notation. Be sure to show all of your work.
6a + 10 > 7a – 1 Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Subtract  from both sides.
 Subtract  from both sides.
 Combine like terms on the left side.
 Combine like terms on the right side.
 Divide both sides by  to isolate  . note: Remember, the inequality sign flips when we divide both sides by a negative number.
 Reduce.
----------------------------------------------------------------------
Answer:
So the solution is
Also, the answer in set-builder notation is
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
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Question 568722: 5(2h-6) -7 ( h+7) 4h Answer by jim_thompson5910(21667) (Show Source):
Question 568717: 5x -7 ( x+1) > -9 Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Distribute.
 Combine like terms on the left side.
 Add  to both sides.
 Combine like terms on the right side.
 Divide both sides by  to isolate  . note: Remember, the inequality sign flips when we divide both sides by a negative number.
 Reduce.
----------------------------------------------------------------------
Answer:
So the solution is
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
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Question 568720: 7x-1 < 9x -26 -2x Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Combine like terms on the right side.
 Add  to both sides.
 Subtract  from both sides.
 Combine like terms on the left side.
 Combine like terms on the right side.
 Simplify
Since the inequality is false, there are no solutions.
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
-------------------------------------------------------------------------------------------------
Question 568553: 15 - 10y < 24 Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Subtract  from both sides.
 Combine like terms on the right side.
 Divide both sides by  to isolate  . note: Remember, the inequality sign flips when we divide both sides by a negative number.
 Reduce.
----------------------------------------------------------------------
Answer:
So the solution is
Which in decimal form is
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
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Question 568218: Explain how to answer this by elimination using multiplication please:
The sum of the digits of a two digit number is 11. If the digits are reversed, the new number is 45 more than the original number. Find the number and show your work. Found 2 solutions by issacodegard, mananth: Answer by issacodegard(60) (Show Source):
You can put this solution on YOUR website!Let the number be N and let its digits be x (tens) and y (ones). Then,

We can create two equations from what's given,

So,

Multiply the 1st eqn by 9 and add it to the second to get,

Divide the second by 9 to get y=8. Then, we have

So,

So, the original number was 38.
Answer by mananth(10539) (Show Source):
You can put this solution on YOUR website!let the digits be x & y x in the tens place and y in the units place
x+y=11
The number is 10x+y
reversed
10y+x
10y+x= 10x+y +45
9y-9x=45
/9
y-x=5
x+y =11
y-x=5
add the two equations
2y=16
/2
x=8
if x = 8 then y= 3
the number is 83
m.ananth@hotmail.ca
Question 568158: Solve using the addition principle.
-18 = m - 30 Answer by jim_thompson5910(21667) (Show Source):
Question 567899: Solve the following inequalities. If there are any identities, say so. If there are any contradictions, say so. Answer using interval notation if possible.
|7x-11|<0 Answer by bucky(2097) (Show Source):
You can put this solution on YOUR website!The problem you are given to solve is:
.

.
This problem contains a contradiction. By definition the absolute value of a quantity must be either zero or positive. It cannot be less than zero (meaning it cannot be negative).
.
So by definition the left side, which entirely an absolute value, must be zero or positive. Therefore it cannot be less than zero as it is shown.
.
I hope this helps you understand the concept of absolute values a little more.
Question 567509: Q: If x in an integer such that 200<3x^3<400, find x. Answer by richard1234(4789) (Show Source):
Question 567508: Q: If x is a positive integer such that 350<7x^2<450, find x. Answer by stanbon(48502) (Show Source):
You can put this solution on YOUR website!x in an integer such that 200<3x^3<400, find x.
-----
Divide thru by "3" to get:
(200/3) < x^3 < (400/3)
----
Take the cube root along the line:
---
cbrt[200/3] < x < cbrt[400/3]
4.0548 < x < 5.1087
---
Answer: 5
==================================
cheers,
Stan H.
Question 567248: Write the following in inequality notation: 2 x + 5 < 5 x -1 Answer by lwsshak3(2900) (Show Source):
You can put this solution on YOUR website!Write the following in inequality notation:
2 x + 5 < 5 x -1
add -5x to both sides
-3x+5<-1
add -5 to both sides
-3x<-6
divide both sides by -3 and reverse inequality sign
x>2
solution:
(2,∞)
Question 567200: how do i solve the inequality x^2x-15<0 algebraically Answer by richard1234(4789) (Show Source):
You can put this solution on YOUR website!Do you mean
 (which cannot really be solved algebraically), or
 , or
or even  ? Make sure you check for errors or ambiguities before you post.
Question 566608: how do I solve to get the inequality when: 2x+4> 1/3
Answer by Theo(2967) (Show Source):
You can put this solution on YOUR website!2x + 4 > 1/3
subtract 4 from both sides of the equation to get:
2x > 1/3 - 4
multiply 4 by 3/3 to get:
2x > 1/3 - 12/3
simplify to get:
2x > -11/3
divide both sides of the equation by 2 to get:
x > -11/(3*2)
simplify to get:
x > -11/6
since this can't be simplified any further, that' your answer.
confirm by substituting for x in your original equation.
pick a value of x > -11/6
pick a value for x that is greater than -11/6.
try -10/6
your original equation is:
2x + 4 > 1/3
substitute -10/6 for x to get:
2 * (-10/6) + 4 > 1/3
simplify to get:
-20/6 + 4 > 1/3
multiply 4 by 6/6 to get:
-20/6 + 24/6 > 1/3
combine like terms to get:
4/6 > 1/3
simplify to get:
2/3 > 1/3
since this equation is true, your value for x is probably good.
to make a complete test, you would need to test out when x = -11/6 and when x < -11/6.
both those tests should lead to a false equation (one that is not true).
for example:
when x = -11/6, the original equation of:
2x + 4 > 1/3 becomes:
2 * (-11/6) + 4 > 1/3
simplify to get:
-22/6 + 4 > 1/3
multiply 4 by 6/6 to get:
-22/6 + 24/6 > 1/3
combine like terms to get:
2/6 > 1/3
simplify to get:
1/3 > 1/3
this equation is false because 1/3 is equal to 1/3 and not greater than it.
the value of x = -11/6 is not valid.
this is correct because the solution to the equation said that x > -11/6, not x = to -11/6 and not x >= -11/6.
Question 566484: the sum of 15 and n is less than 8. Answer by jim_thompson5910(21667) (Show Source):
Question 566374: You have saved a total of more than $75 but less than $120. When you count your money, you find that you have some one dollar bills, some five, and some tens. You have twice as many tens as fives and four times as many ones than fives. How much money could you have? Write equations and/or inequalities (using "t" for ttens, "f" for fives and "n" for ones) in order to solve. Explain your work.
I know I have to start with 2t than 5 + 4x than ones. Now I am stuck. Answer by KMST(576) (Show Source):
You can put this solution on YOUR website!Let  be the number of $1 bills;
let  be the number of $5 bills, and
Let  be the number of $10 bills, as suggested
We start with equations, because some numbers seem to be equal.
We can translate "twice as many tens as fives" as

We can translate "four times as many ones than fives" as
 , although I would have stated that as "four times as many ones as fives."
The total amount of money would be $  , but we can substitute the expressions above to have everything as a function of  , the number of $5 bills.
$  =$  =$  =$ 
So we have $  .
We know that the amount is "more than $75 but less than $120," so
 <--- That's two inequalities in one, but it's OK to write it like this (at least in my book).
So we divide all 3 sides of the inequalities by 29 and get an equivalent double inequality.
 is approximately 2.586 and  is approximately 4.138, but  is suposed to be a natural number (a positive integer).
So it could only be  , or  .
If  , the amount of money you have is $  =$  =$87.
If  , the amount of money you have is $  =$  =$116.
Question 566205: -2/3f+3<-9 Answer by jim_thompson5910(21667) (Show Source):
Question 566117: I am taking and online algebra class in college and my professor gave us a project and one of the questions is to solve this equation:
7[-6+5(-3+5)]
When I do the problem I keep getting -14. However my calculator keeps showing the answer as 28. I feel dumb because it is not a hard problem to figure out but I cannot seem to figure out what the correct answer is. Please help! Answer by Edwin McCravy(6927) (Show Source):
You can put this solution on YOUR website!
Remember "PEMA"
Parentheses, Exponents, Multiplication, Addition. [Remember that division is
a special kind of multiplication, and that subtraction is a special kind of
addition. Some people use "PEMDAS", but that sometimes makes students think
that multiplication comes before division and that addition comes before
subtraction, when it doesn't. That is determined by left takes precedence over
right]
Just do one operation at a time, and copy everything else over and don't skip
steps, and you'll always get the right answer.
7[-6+5(-3+5)]
First we look for Parentheses. The innermost parentheses is (-3+5), so we
replace that by (2) and copy everything else over:
7[-6+5(2)]
We look again for parentheses, the innermost one is now [-6+5(2)], and within
that parentheses we look for a parentheses. We find (2) but there is nothing
to do in that parentheses, so we go next to exponents within that set of
parentheses [-6+5(2)]. There are no exponents in there. So we look for
multiplication and we see 5(2) which we replace by 10 and copy everything else
over:
7[-6+10]
We look again for parentheses, the innermost one is now [-6+10], and within
that parentheses we look for a parentheses. Within that there is only -6+10 to
do, so we replace [-6+10] by [4] and copy everything else over:
7[4]
Finally we multiply 7 by 4 and get 28
Answer: 28
Edwin
Question 566086: Solve the inequality: 3x + 2 ≤ 1 Answer by Alan3354(21542) (Show Source):
Question 566075: Solve the inequality - 4x < -7 Answer by Alan3354(21542) (Show Source):
You can put this solution on YOUR website!Solve the inequality - 4x < -7
----------
Divide by 4
-x < -7/4
Divide by -1, change the < to >
x > 7/4
===========
Or you can view it this way:
- 4x < -7
Add 4x to both sides
0 < 4x - 7
Add 7
7 < 4x
Divide by 4
7/4 < x
x > 7/4
Question 565947: Solve the compound inequality. 3(x-4)<9 or x+1>5 Answer by lwsshak3(2900) (Show Source):
Question 565386: What is the answer to this inequality 3\4 - m >8 Answer by josmiceli(6768) (Show Source):
You can put this solution on YOUR website!
subtract  from both sides

Divide both sides by  and
reverse the inequality sign

--------------
check answer:
Let  ( It is less than -(29/4) )
OK
Question 565211: please help me understand Factoring and Inequalities, problem (x+1)(x+4) Answer by rfer(10417) (Show Source):
Question 565143: What is the answer to
X-9 greater than or equal to -5 Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Add  to both sides.
 Combine like terms on the right side.
----------------------------------------------------------------------
Answer:
So the solution is
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
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Question 565106: To ride an amusement park ride you must be 48 inches or taller
Write the inequality to represent The situation Answer by jim_thompson5910(21667) (Show Source):
Question 565111: |2x+5|-1<6
Answer by jim_thompson5910(21667) (Show Source):
Question 564986: there are n teams in a league and the number of games played is given by the polynomial n^2-n=N. A woman's softball league has 7 teams. what is the total number of games to be played? Answer by ad_alta(170) (Show Source):
Question 564837: Please help me with this:
Solve using the addition and multiplication principles.
34>4-6x Answer by ankor@dixie-net.com(12678) (Show Source):
You can put this solution on YOUR website!34 > 4 - 6x
Add 6x to both sides
6x + 34 > 4
Subtract 34 from both sides
6x > 4 - 34
6x > -30
divide both sides by 6
x > 
x > -5
:
Check solution x > -5, let's say x = -4
34 > 4 - 6(-4)
34 > 4 + 24
34 > 28; which is true
:
However if you try it with x = -6, it will not be true as you would expect
Question 564988: the product of the page numbers on 2 facing pages of a book is 156. find the page numbers. Answer by Alan3354(21542) (Show Source):
You can put this solution on YOUR website!the product of the page numbers on 2 facing pages of a book is 156. find the page numbers.
------------
Factor 156, you'll see it has a 13.
You can make up some equations, but then you have to factor it anyway.
Or use the quadratic eqn.
Question 564749: 3/10(e-2) is less than or equal to 3/5e - 1/4
I'm fairly sure I'm supposed to find the least common denominater (?) for the fractions, which is 20, and would change the fractions to 6/20, 12/20, and 5/20, but if that's right, do I also multiply (e-2) by 20? I'm so confused. Thank you! Answer by lwsshak3(2900) (Show Source):
You can put this solution on YOUR website!3/10(e-2) is less than or equal to 3/5e - 1/4
**
First, I will write the equation I believe is the given problem:
(3/10)(e-2)≤(3/5)e-1/4
3(e-2)/10≤3e/5-1/4
LCD:20 (like you said)
6(e-2)≤12e-5 (yes, you should multiply 6*(e-2))
6e-12)≤12e-5
-6e≤7
Divide by -6 and reverse inequality sign
e≥-7/6
solution in interval notation
[-7/6,∞)
Question 564112: I need help with inequalities.
"Write the following inequality in slope-intercept form."
4x-2y>-24
Thank You! Answer by stanbon(48502) (Show Source):
You can put this solution on YOUR website!I need help with inequalities.
"Write the following inequality in slope-intercept form."
4x-2y>-24
-----
Add 2y to both sides to get:
4x > 2y -24
---
Add 24 to both sides to get:
2y < 4x + 24
----
Divide both sides by 2 to get the slope-intercept form:
y < 2x + 12
=======================
Cheers,
Stan H.
=======================
Question 564091: Hi!
I need help on an inequality involving absolute value. The problem is |(1/x)-3|>6. I broke the inequality into 2 equations, (1/x)-3>6 and (1/x)-3<-6. I then proceeded to get the equations, (1/x)>9 and (1/x)<-3. I am stuck from here. The answer I should get is (-(1/3),0) union (0,(1/9)). Thank you for any help you can give me. Answer by stanbon(48502) (Show Source):
You can put this solution on YOUR website!|(1/x)-3| > 6
---
The problem has 2 parts:
(1/x)-3 > 6 ; (1/x)-3 < -6
------------------------------
(1/x) > 9 ; (1/x) < -3
Notice x must equal 1/10, 1/11, 1/12 etc.(getting closer and closer to zero)
Notice x must equal -1/4, -1/5 , -1/6 etc.(getting closer and closer to zero)
----
-1/3< x < 0 ; 0< x < 1/9
----
Solution: (-1/3 , 0) U (0 , 1/9)
=============================================
Cheers,
Stan H.
Question 564077: I need help with linear inequalities by graphing:
y>-5x+10
y<-2x+15
Thank you! Answer by stanbon(48502) (Show Source):
You can put this solution on YOUR website!y>-5x+10
Draw the boundary as a dashed line:
Plot (0,10) and (2,0) and draw a dashed line thru them:
Shade the half-plane ABOVE the boundary because you
want y GREATER than -5x+10.
----------------------------------------------------
y<-2x+15
Draw the boundary as a dashed line:
Plot (0.15) and (2,11) and draw the boundary.
Shade the half-plane BELOW the boundary because you
want y LESS than -2x+15
===================================
Cheers,
Stan H.
Question 563847: solve:
 Answer by richard1234(4789) (Show Source):
Question 563568: Solve the inequality
x^2+13x>-36
What I did:
x^2+13x>-36 (add 36 to both sides)
x^2+13x+36>0 (Then I factored)
(x+4)(x+9) (this becomes)
x=-4 x=-9 (now I am stuck)
it is either (-9,-4) or (-Inf,-9)U(-4,Inf) I can't figure it out
Answer by richard1234(4789) (Show Source):
You can put this solution on YOUR website!We have (x+4)(x+9) > 0. What you would do is test certain values of x to see which intervals satisfy. For example, suppose x = -5. Then (-5+4)(-5+9)>0, a false statement. Hence the answer is (infinity, -9) U (-4, infinity).
The other method to do is it note that (x+4)(x+9) is a parabola that opens upward, so the part between the roots -4, -9 would be below the x-axis.
Question 563665: I need help..please
Solve and graph the compound inequality.
x+10<-2 or x+10>4 Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!x+10<-2 or x+10>4
x+10-10<-2-10 or x+10-10>4-10
x < -12 or x > -6
So the solution is x < -12 or x > -6 which graphs to
Note:
There is an open circle at  which means that we're excluding that value from the solution set.
Also, there is an open circle at  which means that we're excluding that value from the solution set.
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
-------------------------------------------------------------------------------------------------
Question 563636: -2(2p+6)+5<-3(p-1)
Answer by jim_thompson5910(21667) (Show Source):
You can put this solution on YOUR website!
 Start with the given inequality.
 Distribute.
 Combine like terms on the left side.
 Add  to both sides.
 Add  to both sides.
 Combine like terms on the left side.
 Combine like terms on the right side.
 Divide both sides by  to isolate  . note: Remember, the inequality sign flips when we divide both sides by a negative number.
 Reduce.
----------------------------------------------------------------------
Answer:
So the solution is
-------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com
Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you
Jim
-------------------------------------------------------------------------------------------------
Question 563329: How do you know if a value is a solution for an inequality? How is this different from determining if a value is a solution to an equation?
Answer by richard1234(4789) (Show Source):
Question 563524: Solution to -(10x-1)>96 Answer by fcabanski(385) (Show Source):
You can put this solution on YOUR website!-(10x-1)>96 | Distribute the -1, in other words change the sign of the terms inside ().
-10x + 1 > 96 | subtract 1 from both sides
-10x>95 | Divide by -10. If dividing by a - with an inequality, switch the inequality
x<-9.5
If you need help understanding math so you can solve these problems yourself, then one on one online tutoring is the answer ($30/hr). If you need faster solutions with guaranteed detailed answers, then go with personal problem solving ($3.50-$5.50 per problem). Contact me at fcabanski@hotmail.com
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