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Question 240530

-8(x-3) +12x= 15-(2x +3)

answer: -2 (anyone can show me why the answer is -2 and can give a full break down thank you).

Found 2 solutions by scott8148, solver91311:

Answer by scott8148(3385)

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distributing ___ -8x + 24 + 12x = 15 - 2x - 3

collecting terms ___ 4x + 24 = -2x + 12

adding 2x and subtracting 24 ___ 6x = -12

dividing by 6 ___ x = -2

Answer by solver91311(5072)

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Distribute to remove parentheses. Remember

has a coefficient of -1.

Collect like terms:

Add

to both sides and add

to both sides:

Collect like terms:

Multiply both sides by the reciprocal of the coefficient on the variable, namely

John

Question 240499: determine the value of "r" so that the line passes through each pair of points at the given slope.
(7,-5), (6,r),m=0
Please Help !
Answer by jim_thompson5910(13794)

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Hint: the slope formula is

. So plug in the given coordinates and the slope to get

and simplify to get

. Now solve for 'r' to get

-->

So the second y coordinate is -5. It turns out that to have a slope of zero, the y coordinates must be the same.

Question 239973: how do you get 24 using onlt three operations with the numbers 8 8 6 1 using the numbers only once
Answer by Edwin McCravy(2922)

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Question 239832: what is the difference?
-5^2 - I thought the answer is 25
(-5)^2 - I thought the answer is 25
-(5)^2 - I thought the answer is -25

Answer by checkley77(7072)

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-5^2 - I thought the answer is 25
(-5)^2 - I thought the answer is 25
-(5)^2 - I thought the answer is -25
--------------------
-5^2=-(5*5)=-25 ans.
(-5)^2=(-5*-5)=25 ans.
-(5)^2=-(5*5)=-25 ans.

Question 239444: I have a question regarding this solved problem on the site -
Answer by jim_thompson5910(13774)
The question was Combine like terms 5w - 6w and the answer said, 5w - 6w = -1w which also looks like 5w - 6w = -w.
Why do you remove the 1? How do you know when to do that? My daughter and I are confused about this.
thank you - karen gass
Answer by solver91311(5072)

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You can ALWAYS leave off a coefficient of 1. Just remember that a 1 coefficient is always understood to be there whether you see it or not.

has a

coefficient. Which is to say that

for any number

.

John

Question 239084: how do i get 24 using the numbers 9,8,7, and 6 and i have to use addition, subtraction, multiplication, and division just once
Answer by checkley77(7072)

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6*8/(9-7)=48/2=24

Question 238846: what is 6mt + t can it be simplified
and
2w-(5w-a)+6a
Answer by unlockmath(121)

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Hello,
You can put 6mt + t into this form:
t(6m+1)
and the other one can be simplified to:
2w-5w+a+6a which can be further simplified to:
-3w+7a
RJ Toftness
www.math-unlock.com

Question 237225: may i know what is the corrrect process for solving this problem?
the question is:
20/(3(2x-8)-(-56)/7)
thank you so much.
Answer by rapaljer(3625)

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This one sure looks UGLY, but a lot of problems are just made to LOOK that way--they really are not as bad as they LOOK!!

First, divide the fraction (-56)/7 =-8, and remember that -(-8)=+8.

Next, you have
20/(3(2x-8)-(-56)/7)
20/(3(2x-8+8))
20/(3(2x))
20/(6x)

Divide out a factor of 2:
10/(3x)

Dr. Robert J. Rapalje

Question 236975: Hello, I can't figure out these 2 problems using Pemdas. Use each operation only once per problem (addition, subtraction, division and multiplication).Thank you!!!
12___6___4___2=24
12___6___4___2=14
Answer by RAY100(1637)

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12 + 6 * 4 / 2
.
12 + 24/2
.
12 + 12
.
24
.
.
.
12-6 +4 * 2
.
12-6 + 8
.
6+8
.
14
.

Question 234403: I have a question regarding order of operations:
how do i solve this problem:
59-35/7*4+53
Answer by kennysmom(1)

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59-(35\7)*4+53
35\7=5
59-5*4+53
59-20+53
92

Question 232911: can you help me solve this -14
-23
Answer by rfer(2688)

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-14-23=-37

Question 232639: tell whether the given value of the variable is a solution of the equation -5r=125;r=-15
Answer by Alan3354(6097)

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tell whether the given value of the variable is a solution of the equation -5r=125;r=-15
----------
-5r = 125
Sub -15 for r
-5*-15 =? 125
75 =? 125
No, it doesn't, so it's not a solution.

Question 231716: i need help with my homework

Answer by bamaboy(14)

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post it retard

Question 230479: How do I get my answer to equal 1 when the only numbers I have to use are 10,9,8,6,5. I can multiply,divide,subtract,and add. I have tried all the adding and subtracting ways. I have also tried getting the numbers to go negative so I can get it up to one.
Found 3 solutions by solver91311, Earlsdon, stanbon:
Answer by solver91311(5072)   (Show Source):
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You didn't specify all of the rules. But I'm going to presume that you cannot use any of the numbers more than once and that you have to use all of them.

John

Answer by Earlsdon(4900)   (Show Source):
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How about this?
=

Answer by stanbon(26297)   (Show Source):
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How do I get my answer to equal 1 when the only numbers I have to use are 10,9,8,6,5. I can multiply,divide,subtract,and add.
-----------------------------
[(9+6)/5]-[10-8] = 3-2 = 1
================================
Cheers,
Stan H.

Question 229883: HI, my name is Donesha. I want to ask a simple question about negative an positive numbers.
So say,
What would these equal:
(+)+(+)=
(+)-(+)=
(+)*(+)=
(+)/(+)=
(-)+(-)=
(-)-(-)=
(-)*(-)=
(-)/(-)=
Found 2 solutions by jsmallt9, stanbon:
Answer by jsmallt9(594)   (Show Source):
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What would these equal:
(+)+(+)= Always positive
(+)-(+)= Positive if the first number is larger, negative if the first is smaller, zero if the numbers are the same
(+)*(+)= Always positive
(+)/(+)= Always positive
(-)+(-)= Always negative
(-)-(-)= Negative if the absolute value of the first is larger, Positive if the absolute value of the first is smaller and zero if the numbers are the same
(-)*(-)= Always positive
(-)/(-)= Always positive

As you can see, the rules for subtractions are not simple. For this reason and others, I encourage everyone to learn how to change subtractions into additions. Then you only have to know how to add.

Answer by stanbon(26297)   (Show Source):
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What would these equal:
(+)+(+)= +
(+)-(+)= depends : 3-4 is negative ; 4-3 is positive
(+)*(+)= +
(+)/(+)= +
(-)+(-)= -
(-)-(-)= depends : -3--4 is positive ; -4--3 is negative
(-)*(-)= +
(-)/(-)= +
==============
Cheers,
Stan H.

Question 229793: what is the algebraic expression for three fourths the square of b
Answer by Alan3354(6097)   (Show Source):
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Question 229313: how do i solve 1/2v= -1/2v + 3/8
Answer by shymeerab(21)   (Show Source):
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1/2v= -1/2v + 3/8
1/2v+1/2v=3/8
2/2v=3/8
1/v=3/8
v=8/3

Question 228470: How do you right 5m in two word phrases?
Answer by rapaljer(3625)   (Show Source):
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How about "five meters"?? Is that what you mean? That is the best I can think of.

Question 227211: I'm in the 6th grade.My question is:Integer rules when the signs are different you are supposed to subtract,are they talking about the signs in paranthes
EX is (+9)+(-8)= the two signs are different so do i just subtract both now,because the signs in parantheses are different
Answer by Theo(675)   (Show Source):
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(+9) + (-8) is the same as (+9) - (+8).

You would subtract.

the answer is 9 - 8 = 1

It's the operator combined with the sign that determines what you do.

The sign is within the parentheses. It tells you whether the number is negative or positive.

the operator is outside the parentheses. It tells you whether you will be adding or subtracting.

adding a negative number is the same as subtracting a positive number.

+ (-9) is the same as - (+9)

when you combine the operator with the sign, the rules are:

++ means add
+- means subtract
-+ means subtract
-- means add

the first sign is the operator.

the second sign is the sign of the operand (the number you are working on).

check the following website out.

It might help clarify it.

Adding and Subtracting Positive and Negative Numbers

Question 226662: Please help me solve this equation: 14=16t^2+12t
Answer by drj(1380)   (Show Source):
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Please help me solve this equation:

Step 1. Subtract 14 from both sides of the equation.

Step 2. To solve, use the quadratic equation given as

where a=16, b=12, and c=-14

Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=1040 is greater than zero. That means that there are two solutions: .

Quadratic expression can be factored:

Again, the answer is: 0.632782218537319, -1.38278221853732. Here's your graph:

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV

Question 225305: what is: 3x+10=2x-5
Answer by LtAurora(115)   (Show Source):
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We need to get the #s on one side and the x terms on the other.
So, move the 10 to the other side by subtracting it from both:

Then move the 2x over to the other side by subtracting it from both sides:

, which is our answer.

Question 223844: so i have this test tomorrow and i do not understand how to determine what r equals.PLEASE HELP ME!
so the question says determine the value of r so that the line passes through each pair of points has the given slope.
(r,4)(7,1)with m=3/4.
step by step how do i solve this??
Found 2 solutions by MathTherapy, rfer:
Answer by MathTherapy(336)   (Show Source):
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so i have this test tomorrow and i do not understand how to determine what r equals.PLEASE HELP ME!
so the question says determine the value of r so that the line passes through each pair of points has the given slope.
(r,4)(7,1)with m=3/4.
step by step how do i solve this??

The slope of any equation is determined by the slope formula, or m, which = , where in this case, . Since it's given that m, or the slope = , then we'll have:

3(7 - r) = 4(- 3) ------ Cross-multiplying to get rid of denominators

21 - 3r = - 12

- 3r = - 33

r = , or, r =

Answer by rfer(2688)   (Show Source):
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here goes.
plot (7,1) then use the slope to find the next point
from (7,1) go four to the right and three up to(11,4)
slope=m=3/4
rise over run
Does that help?
Bob

Question 223558: For order of operations, what is the correct way to solve this problem? The answer key says 9, but I get 33. What is the correct way to do this problem and why?
36 ÷ 4(5-2)+ 6
Found 2 solutions by MathTherapy, drj:
Answer by MathTherapy(336)   (Show Source):
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For order of operations, what is the correct way to solve this problem? The answer key says 9, but I get 33. What is the correct way to do this problem and why?

36 ÷ 4(5 - 2) + 6

36 ÷ 4(3) + 6 ------ Working out expression in parentheses

36 ÷ 12 + 6 ----- Multiplying to get rid of parentheses

3 + 6 = ----- Applying PEMDAS (Division before addition)

Answer by drj(1380)   (Show Source):
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For order of operations, what is the correct way to solve this problem? The answer key says 9, but I get 33. What is the correct way to do this problem and why?

36 ÷ 4(5-2)+ 6

Step 1. Do the operation in the parenthesis

36 ÷ 4(3)+ 6

Step 2. Perform 36/4=9

Step 3. 9*3=27

Step 4. 27+6=33 I get the same answer as you!

I think how they got nine is as follows

36/12+6=9 But this is not correct as written. It should be written with an additional set of parenthesis given as follows:

36 ÷ (4(5-2))+ 6

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

Good luck in your studies!

Respectfully,
Dr J

Question 222350: okay I have a order of operations number question and I have to simplify. It's
I need a step by step on how to do this, please
Answer by Edwin McCravy(2922)   (Show Source):
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Write the first term as a division: Invert the and change the division sign before it to a multiplication sign: Cancel the 3 into the 12 getting Multiply the 2 by the 4, getting 8, and put that over 7 for the first term: Combine the first two terms which gives The least common denominator of and is So we multiply by and get and we multiply by and get Now add the numerators getting and place that over the LCD of If your teacher accepts improper fractions, leave it like that, or change it to a mixed number Edwin

Question 221898: -1.56 - -3.2
I'm having trouble with this problem, please help. Thanks
Answer by likaaka(51)   (Show Source):
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If you are having difficulties understanding negative numbers, here's an analogy that I use to remember them:
Let "good" be "positive" and "bad" be "negative"
good things happening to good people: a good thing
good things happening to bad people: a bad thing
bad things happening to good people: a bad thing
bad things happening to bad people: a good thing
So what you have in the back of the problem, - -3.2, can be seen as a bad thing happening to a bad person, which is a good thing and therefore translates to +3.2
The proper mathematical explanation is the minus of a minus is a plus rule.
-1.5 - -3.2
-1.5 + 3.2
Next, using the commutative property of addition, I would rearrange the problem so that the larger number, in this case the positive 3.2, is first and the smaller number, in this case the negative 1.5, is at the end
-1.5 + 3.2
3.2 + -1.5
So what you have now in the back of the problem, + -1.5, can be seen as a good thing happening to a bad person, which is a bad thing and therefore translates to -1.5
So
3.2 + -1.5
3.2 - 1.5, now perform the indicated operation
3.2 - 1.5 = 1.7
Hope this helps

Question 221897: -1.2(-1.09)
I tried to solve this but I just keep getting messed up. So if someone could help me with this, that would be awesome! Thanks
Found 2 solutions by checkley77, Alan3354:
Answer by checkley77(7072)   (Show Source):
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-1.2(-1.09)=1.308 ans.

Answer by Alan3354(6097)   (Show Source):
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-1.2(-1.09)
= -1*-1*1.2*1.09
= 1.2*1.09
1.308

Question 220889: What is (x+5y) + (x-y)
Answer by edjones(3299)   (Show Source):
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x+x=2x
5y-y=4y
2x+4y Answer.
.
Ed

Question 220214: Okay. Heres a question I absolutely do NOT get.
If a certain number is decreased by 8 and that difference is multiplied by 8, the result is equal to the result obtained if the number is decreased by 6 and that difference is multiplied by 6. Find the numbers.
In my opinion this is a make-believe question :(
Help please.
Answer by solver91311(5072)   (Show Source):
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I'm not certain what you mean by a 'make-believe' question. Virtually every mathematics word problem is a contrivance of some sort to illustrate one or more mathematical concepts. This one is no exception.

Let represent the number. The number decreased by 8 is then which expression is the difference. Multiplying this difference by 8 gives us: . Likewise 6 times the difference of the number and 6 is: . We are given that these two quantities are equal so:

All you need to do now is solve the equation for

John

Question 219906: Hi, my names Marlene and I am having trouble with this problem in Pre-Algebra. It is order of operations just looking at it confuses me. Here it is...
(100-85)x5+81/9x2-3(72-60)/4-(11+5)+5x9/3=
Found 2 solutions by MathTherapy, rfer:
Answer by MathTherapy(336)   (Show Source):
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Hi, my names Marlene and I am having trouble with this problem in Pre-Algebra. It is order of operations just looking at it confuses me. Here it is...
(100-85)x5+81/9x2-3(72-60)/4-(11+5)+5x9/3=

75 + 18 - 9 - 16 + 15 ---- 75 + 18 + 15 - 9 - 16 ---- 108 - 25 =

Answer by rfer(2688)   (Show Source):
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(100-85)x5+81/9x2-3(72-60)/4-(11+5)x9/3
please excuse my dear aunt sally from left to right
15x5+81/9x2-36/4-16+45/3=
75+9x2-9-61+15=
75+18-70+15=38

Question 219574:
I'm not sure how they excpect me to divide by zero, would the answer simpliy be zero?
Please help, and thank you.
Found 2 solutions by jsmallt9, jim_thompson5910:
Answer by jsmallt9(594)   (Show Source):
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I'm glad you recognize that dividing by zero is impossible/undefined. (It is not 0!)

You'll have to post the rest of the problem so we can see how you ended up with . If is correct it may mean something in the context of the overall problem. For example, if you are calculating the slope of a line, an answer of means the slope is undefined. And lines with undefined slopes are vertical lines. (Vertical lines have equations of the form x = a where "a" is the x coordinate of any point on the line. (All the x coordinates on a vertical line are the same!))

Or perhaps an error was made and you should not end up with .

Answer by jim_thompson5910(13794)   (Show Source):
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You CANNOT divide by zero. The answer is undefined.

Question 219564: Simplify:
I'm lost when it comes to this problem, I just dont understand how I should simplify it.
Answer by jim_thompson5910(13794)   (Show Source):
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Any number divided by itself is simply 1. So this means

Question 219553: (10)(-9)(8)(-7)(6)(-5)0
If I try to solve this the way I think it should be the answer comes out as 0 and I'm not sure if thats correct and if I'm doing it the right way. Please help if you can, thank you.
Answer by jim_thompson5910(13794)   (Show Source):
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You are correct. Anything multiplied by zero is zero. So you could have a million terms multiplied here, but just multiply that whole mess by zero will get you zero (regardless of what you got beforehand).

Question 218372: One of the wrenches has a measurement of 7/16” and the other has a size of 3/8”. Which one is larger?
Answer by jim_thompson5910(13794)   (Show Source):
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Solved by pluggable solver: Compare two Ratios

To compare two ratios, we can use cross multiplication. We can arrive at the answer in the following way:

?

Cross multiplying:
7*8 ? 3*16
=> 56 ? 48
since 56 > 48, we get that >

So this means that the 7/16" wrench is larger.

Question 218306: The number midway between -6 and 2 is ________?
I'm not confident that I know how to solve this the right way, please help if you can.
Thank you!
Answer by RAY100(1637)   (Show Source):
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Midpoint is (X1+X2)/2
.
in this case {-6+2}/2 =-4/2=-2
.
check,, distance from -6 to -2 is 4,,,,,and distance from +2 to-2 is also 4
.
.
.
Lets use a simple example ,,,,4,5,6,,,obviously 5 is midpoint,
.
to use math,,we could do,,,6-4 =2,,,and 2/2=1,,and then 6-1=5,,or 4+1=5
.
but it is easier to do (4+6) = 10,,,,10/2=5
.

Question 218303: 1. we have learned that the associative property does not hold for subtraction.
That is, in general,
(a - b) - c ≠ a - (b - c).
Your task is to:
a. find distinct ingtegers a,b,c such that (a - b) - c = a - (b - c).
b. PROVE that your integers work by substituting and simplifying the equation.
Answer by solver91311(5072)   (Show Source):
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Pick anything you like for and , then pick

John

Question 216813: 3x+15 over 5 is equal to 2x-1 solve for x
Answer by MathTherapy(336)   (Show Source):
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3x+15 over 5 is equal to 2x-1 solve for x

3x + 15 = 5(2x - 1) ------ Multiplying each side of equation by LCD, 5

3x + 15 = 10x - 5

3x - 10x = - 5 - 15

- 7x = - 20

, or