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Tutors Answer Your Questions about Radicals (FREE)
Question 168330: problem states: 3X+4Xsquared divided by X to the negative 2/3 power. please show how to remove the -2/3 power of X that is in the denominator.: problem states: 3X+4Xsquared divided by X to the negative 2/3 power. please show how to remove the -2/3 power of X that is in the denominator. Answer by Mathtut(308) (Show Source): |
Question 168292: [SQRT(x + 7)] - 2[SQRT(x)] =-2
I know x = 9
but I am not sure how to get there.
How tall is a stack of cube-shaped blocks whose volumes are 375 cubic inches, 648 cubic inches and 1,029 cubic inches?
A. 10 cubert(3)
B. 6 cubert(3)
C. 3 sqrt(3)
D. 4 sqrt(3)
E. 9 sqt(3)
F. 18 cubert(3): [SQRT(x + 7)] - 2[SQRT(x)] =-2
I know x = 9
but I am not sure how to get there.
How tall is a stack of cube-shaped blocks whose volumes are 375 cubic inches, 648 cubic inches and 1,029 cubic inches?
A. 10 cubert(3)
B. 6 cubert(3)
C. 3 sqrt(3)
D. 4 sqrt(3)
E. 9 sqt(3)
F. 18 cubert(3) Answer by Alan3354(1178) (Show Source):
You can put this solution on YOUR website! [SQRT(x + 7)] - 2[SQRT(x)] =-2
I know x = 9
--------------
The simplest way is to get one radical by itself, then square both sides.
[SQRT(x + 7)] - 2[SQRT(x)] =-2

Now square

Now isolate the other radical

Square again
| Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc) |
Quadratic equation (in our case ) has the following solutons:
![x[12] = (b+-sqrt( b^2-4ac ))/2\a](/cgi-bin/plot-formula.mpl?expression=x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca&x=0003)
For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=6400 is greater than zero. That means that there are two solutions: .
![x[1] = (-(-82)+sqrt( 6400 ))/2\9 = 9](/cgi-bin/plot-formula.mpl?expression=x%5B1%5D+=+%28-%28-82%29%2Bsqrt%28+6400+%29%29%2F2%5C9+=+9&x=0003)
![x[2] = (-(-82)-sqrt( 6400 ))/2\9 = 0.111111111111111](/cgi-bin/plot-formula.mpl?expression=x%5B2%5D+=+%28-%28-82%29-sqrt%28+6400+%29%29%2F2%5C9+=+0.111111111111111&x=0003)
Quadratic expression can be factored:

Again, the answer is: 9, 0.111111111111111.
Here's your graph:
 | |
The onsite solver doesn't do factors correctly if the coefficient of the the x^2 is not 1, but the answers are right, 9 and 1/9.
---------------------------------------
How tall is a stack of cube-shaped blocks whose volumes are 375 cubic inches, 648 cubic inches and 1,029 cubic inches?
A. 10 cubert(3)
B. 6 cubert(3)
C. 3 sqrt(3)
D. 4 sqrt(3)
E. 9 sqt(3)
F. 18 cubert(3)
-------------------
I don't know what you mean by that. More info is needed.
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Question 168091: Evaluate √9/16(fraction), if possible.: Evaluate √9/16(fraction), if possible. Answer by jojo14344(809) (Show Source): |
Question 167724: Simplify:
√[121x^12y^16z^6]
: Simplify:
√[121x^12y^16z^6]
Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website! Start with the given expression
 Rewrite  as  .
 Rewrite  as  .
 Rewrite  as  .
 Rewrite  as  .
 Break up the square root.
 Take the square root of the squares to eliminate the squares. In other words,
So  where every variable is positive
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Question 167726: Rationalize the denominator:
7/√[3] – √[2]
: Rationalize the denominator:
7/√[3] – √[2]
Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website! Start with the given expression
 Multiply both numerator and denominator by the conjugate of the denominator
 Combine the fractions.
 FOIL (hint: use the difference of squares)
 Square each value
 Combine like terms.
 Simplify
 Distribute
So
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Question 167726: Rationalize the denominator:
7/√[3] – √[2]
: Rationalize the denominator:
7/√[3] – √[2]
Answer by CeCe_101(1) (Show Source): |
Question 167727: Multiply:
(5√[3] + √[5])(√[3] – 2√[5])
: Multiply:
(5√[3] + √[5])(√[3] – 2√[5])
Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website!
 Start with the given expression.
Now let's FOIL the expression.
Remember, when you FOIL an expression, you follow this procedure:
 Multiply the First terms:  .
 Multiply the Outer terms:  .
 Multiply the Inner terms:  .
 Multiply the Last terms:  .
---------------------------------------------------
 Now collect every term to make a single expression.
 Now combine like terms.
So  FOILs to  .
In other words,  .
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Question 167725: Perform the indicated operations:
4√[50] + √[32] – √[18]
: Perform the indicated operations:
4√[50] + √[32] – √[18]
Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website!
 Start with the given expression
 Simplify  to get  . Note: If you need help with simplifying square roots, check out this solver.
 Simplify  to get  .
 Simplify  to get  .
 Multiply 4 and 5 to get 20.
Since we have the common term  , we can combine like terms
 Combine like terms. Remember,
 Now simplify  to get
So  simplifies to  .
In other words,
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Question 167503This question is from textbook beginning Algebra
: Please help solve with radicals, Thank You, and please show work
square root of 5x+11= x+3This question is from textbook beginning Algebra
: Please help solve with radicals, Thank You, and please show work
square root of 5x+11= x+3 Answer by sowmya(18) (Show Source):
You can put this solution on YOUR website!square root of 5x+11= x+3
5x+11= (x+3)^2 = x^2 + 9 +6x
5x+11 = x^2 + 6x+ 9
x^2 + x - 2 = 0
x = 1 or x=-2
(solve the quadratic equation and use the formula
x = (-b+-sqrt(b^2-4ac))/2a
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Question 167504This question is from textbook beginning Algebra
: Another solving equations with radicals, please show work, Thank You
square root of x+2 then -2=xThis question is from textbook beginning Algebra
: Another solving equations with radicals, please show work, Thank You
square root of x+2 then -2=x Answer by midwood_trail(221) (Show Source):
You can put this solution on YOUR website!We have this: sqrt{x + 2} - 2 = x
We want to isolate the square root.
So, add 2 to both sides.
We now have this:
sqrt{x + 2} = x + 2
To remove the square root symbol, square both sides.
Doing so, we get this:
x + 2 = x^2 + 4x + 4
x^2 + 4x - x + 4 - 2 = 0
x^2 + 3x + 2 = 0
Factor this quadratic equation.
(x + 1) (x + 2) = 0
Set each factor to zero and solve for x.
x + 1 = 0
x = -1
=========================
x + 2 = 0
x = -2
==========================
To know for sure that we found the right answers, you must check.
Go back to your original question and replace x with -1 and simplify and then with -2 and simplify again. We want to get the same answer on both sides.
You were given:
sqrt{x + 2} - 2 = x
Let x = -1
sqrt{-1 + 2} - 2 = -1
sqrt{1} - 2 = -1
1 - 2 = -1
-1 = -1...IT CHECKS!!!
So, we know that x = -1.
How about x = -2? Is that true?
Let's check again.
Let x = -2.
sqrt{-2 + 2} - 2 = -2
sqrt{0} - 2 = -2
0 - 2 = -2
-2 = -2...IT ALSO CHECKS!!!
We now know that x = -2 is also a value for x.
Final answer: x = -1 and x = -2
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Question 167305: f=1/2pi*sqrt of LC if L=6.224*10^-5 and C=4.1*10^-10. Solve for f
So far, all I've been able to establish is LC=2.55184*10^-15...is this correct and how do I solve the rest?: f=1/2pi*sqrt of LC if L=6.224*10^-5 and C=4.1*10^-10. Solve for f
So far, all I've been able to establish is LC=2.55184*10^-15...is this correct and how do I solve the rest? Answer by Fombitz(1740) (Show Source): |
Question 167316: sqrtof 9x+81=x+5
not sure how to solve...please help: sqrtof 9x+81=x+5
not sure how to solve...please help Answer by ankor@dixie-net.com(4484) (Show Source):
You can put this solution on YOUR website! = x + 5
Square both sides:
9x + 81 = (x + 5)^2
:
FOIL the right side
9x + 81 = x^2 + 10x + 25
:
0 = x^2 + 10x - 9x + 25 - 81
:
A quadratic equation:
x^2 + x - 56 = 0
Factors to:
(x+8)(x-7) = 0
Two solutions
x = -8
and
x = 7
:
Both solutions have to be checked in the original equation:
x= -8
 = -8 + 5
 = -8 + 5
 = -3
3 does not = -3; x = -8 is not a solution
:
x=+7
 = 7 + 5
 = 12
 = 12
12 = 12; x=7 is good solution
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Question 167316: sqrtof 9x+81=x+5
not sure how to solve...please help: sqrtof 9x+81=x+5
not sure how to solve...please help Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website! Start with the given equation
 Square both sides to get rid of the square root.
 FOIL
 Subtract 9x from both sides. Subtract 81 from both sides.
 Combine like terms.
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Square  to get  .
 Multiply  to get
 Rewrite  as
 Add  to  to get
 Multiply  and  to get  .
 Take the square root of  to get  .
 or  Break up the expression.
 or  Combine like terms.
 or  Simplify.
So the possible answers are  or
However, if you plug in  , then the equation won't be true.
=============================================
Answer:
So the only solution is
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Question 166893: 3 √13/3
Simplify: 3 ( square root of 13 over 3)
This is the same question. Just wasnt sure about the best way to present it.: 3 √13/3
Simplify: 3 ( square root of 13 over 3)
This is the same question. Just wasnt sure about the best way to present it. Answer by MRperkins(74) (Show Source):
You can put this solution on YOUR website!
the 3 in the numerator (top number) reduces with the 3 in the denominator and you are left with  or simply 
.
.
.
If the problem reads  then you will get a different answer.
in this case you will rewrite the fraction as the sqrt of the numerator over the sqrt of the denominator. So it would look like this: 
.
now you have 3 to the 1st power on the top and 3 to the 1/2 power on the bottom. These reduce to 3 to the 1/2 power on top and 3 to the 0 power(which is 1) on the bottom. now you can rewrite 3 to the 1/2 power as a sqrt. The formula now looks like this: 
you can multiply these to get  . Since you can not pull any factors out then you should combine the terms and get:
.
look at both examples to make sure you see the differences. Then pick the example that matches your problem.
.
I hope this helps!
.
Private tutoring is available. Click on my name to go to my website or email me at justin.sheppard.tech@hotmail.com for more information. If you have any other questions you can direct them to me personally and I will answer them for you.
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Question 166893: 3 √13/3
Simplify: 3 ( square root of 13 over 3)
This is the same question. Just wasnt sure about the best way to present it.: 3 √13/3
Simplify: 3 ( square root of 13 over 3)
This is the same question. Just wasnt sure about the best way to present it. Answer by Alan3354(1178) (Show Source): |
Question 166804: Can someone help
the hypotenuse of a right triangle is 2.5 units long. The longer leg is 1.3 units longer then the shorter leg. Find the lengths of the sides of the triangle.: Can someone help
the hypotenuse of a right triangle is 2.5 units long. The longer leg is 1.3 units longer then the shorter leg. Find the lengths of the sides of the triangle. Answer by ankor@dixie-net.com(4484) (Show Source):
You can put this solution on YOUR website!the hypotenuse of a right triangle is 2.5 units long. The longer leg is 1.3 units longer then the shorter leg. Find the lengths of the sides.
:
Remember our old friend; a^2 + b^2 = c^2
:
Let x = the shorter leg
then
(x+1.3) = the longer leg:
:
Replace a & b with these expressions, replace c with 2.5
:
x^2 + (x+1.3)^2 = 2.5^2
:
x^2 + (x^2 + 2.6x + 1.69) = 6.25
:
x^2 + x^2 + 3.6x + 1.69 - 6.25 = 0; arrange to form a quadratic equation
:
2x^2 + 3.6x - 4.56 = 0
:
Using the quadratic equation, a=2; b=3.6; c=-4.56
x ~ .9938 ~ 1; the shorter leg
and
1 + 1.3 = 2.3; the longer leg
:
Check solution with calc; enter  = 2.508 ~ 2.5
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Question 166708: Find the dimensions of a rectangle (a) with the greatest area whose perimeter is 30 feet.: Find the dimensions of a rectangle (a) with the greatest area whose perimeter is 30 feet. Answer by Alan3354(1178) (Show Source):
You can put this solution on YOUR website!Find the dimensions of a rectangle (a) with the greatest area whose perimeter is 30 feet.
Area = Length * Width
Perimeter = 2L + 2W = 30
------------------
L+W = 15
W = 15-L
Area = L*W = L*(15-L)
A = 15L - L^2
To find the maximum, set the 1st derivative to zero
15 - 2L = 0
L = 7.5
W = 7.5
The max area for a rectangle is a square, always. The max area for a given perimeter is a circle.
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Question 163585: I know I have to rationalize the denominator, im just not sure how it works with a square root and real number. Help, please! Thanks, Elizabeth.
11
-------
√7 + 8
and
3
--------
2√5 - √7
: I know I have to rationalize the denominator, im just not sure how it works with a square root and real number. Help, please! Thanks, Elizabeth.
11
-------
√7 + 8
and
3
--------
2√5 - √7
Answer by Alan3354(1178) (Show Source):
You can put this solution on YOUR website!I know I have to rationalize the denominator, im just not sure how it works with a square root and real number. Help, please! Thanks, Elizabeth.
11
-------
√7 + 8
//////////////////
Use the "conjugate" to get rid of radicals in the DEN. Multiply NUM and DEN by 
[11*(sqrt(7) -8]/(7 - 64)
= - 
Multiplying by the "conjugate" is something you'll see more of to deal with radicals and imaginaries.
and
3
--------
2√5 - √7
----------------
Same approach, multiply by 
= 
=
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Question 166539: the square root of 4e^3g x the square root of 6eg^2: the square root of 4e^3g x the square root of 6eg^2 Answer by Alan3354(1178) (Show Source):
You can put this solution on YOUR website!the square root of 4e^3g x the square root of 6eg^2
------------------
Multiply the coefficients: 4*6 = 24
Add the exponents of e: 3g + g^2 = g^2 + 3g
That's
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Question 166502: (2sqrt3 + 4 sqrt 2)-(4 sqrt 2 - 3sqrt3): (2sqrt3 + 4 sqrt 2)-(4 sqrt 2 - 3sqrt3) Answer by jim_thompson5910(9162) (Show Source): |
Question 166064: [(squareroot of 3) + (square root of 5)] to exponent of 2: [(squareroot of 3) + (square root of 5)] to exponent of 2 Answer by checkley77(3380) (Show Source): |
Question 166011: how would you go about solving this problem?
7 sqrt12 + 10 sqrt48: how would you go about solving this problem?
7 sqrt12 + 10 sqrt48 Answer by checkley77(3380) (Show Source): |
Question 166014: how would you go about solving this problem?
7 sqrt12 + 10 sqrt48: how would you go about solving this problem?
7 sqrt12 + 10 sqrt48 Answer by ankor@dixie-net.com(4484) (Show Source):
You can put this solution on YOUR website!how would you go about solving this problem?
7 sqrt12 + 10 sqrt48
;
Not exactly solving, You can simplify it, by factoring etc.
:
7*  + 10* 
:
factor inside the radicals to reveal the perfect squares\
7*  + 10* 
:
Extract those perfect squares
7*2*  + 10*4 
which is
14*  + 40* 
:
Now we have like terms so just add em up
54*
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Question 165558: What steps would you take to simplify this problem:
(2 √(x-5))(3 √(x+1)) where the x-5 and the x+1 are both completely under the radical sign.: What steps would you take to simplify this problem:
(2 √(x-5))(3 √(x+1)) where the x-5 and the x+1 are both completely under the radical sign. Answer by edjones(2391) (Show Source): |
Question 165613: ^3{sqrt x+1}=5: ^3{sqrt x+1}=5 Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website! Start with the given equation
 Cube both sides to eliminate the cube root.
 Cube 5 to get 125
 Subtract  from both sides.
 Combine like terms on the right side.
----------------------------------------------------------------------
Answer:
So the answer is
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Question 165609: 3 {sqrt 3}/ {sqrt 6}: 3 {sqrt 3}/ {sqrt 6} Answer by nerdybill(1040) (Show Source):
You can put this solution on YOUR website! 3 {sqrt 3}/ {sqrt 6}
Factor the number inside the radical:
3 {sqrt 3}/ {sqrt 2*3}
ReWriting it as:
3 {sqrt 3}/[{sqrt 2}{sqrt 3}]
Canceling like-terms:
3/{sqrt 2}
Multiplying numerator and denominator by {sqrt 2}:
3{sqrt 2}/2
Rewriting:
(3/2){sqrt 2}
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Question 165610: 2 {sqrt x^3} + 5x{sqrt x} - 3{sqrt x^5}: 2 {sqrt x^3} + 5x{sqrt x} - 3{sqrt x^5} Answer by nerdybill(1040) (Show Source):
You can put this solution on YOUR website! 2 {sqrt x^3} + 5x{sqrt x} - 3{sqrt x^5}
You can rewrite as:
2 {sqrt x*x*x} + 5x{sqrt x} - 3{sqrt x*x*x*x*x}
Now, you can "pull out" pairs:
2x {sqrt x} + 5x{sqrt x} - 3x^2{sqrt x}
Factor out the sqrt x:
{sqrt x}[2x + 5x - 3x^2]
Combine like-terms:
{sqrt x}[7x - 3x^2]
Pull out the 'x':
x{sqrt x}[7-3x]
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Question 165407: :  Answer by Edwin McCravy(2033) (Show Source):
You can put this solution on YOUR website!
The index of a square root is 2, so we write:
Divide the index into each exponent.
Divide index 2 into the first exponent 99
49
2)99
98
1
49 is the quotient, so we will have on
the outside in front of the radical.
1 is the remainder, so we will have left
under the radical. So far we have this:

---
Divide index 2 into the second exponent 87
43
2)87
86
1
43 is the quotient, so we will have on
the outside in front of the radical.
1 is the remainder, so we will have left
under the radical. So far we have this:

---
Divide index 2 into the third exponent 64
32
2)64
64
0
32 is the quotient, so we will have on
the outside in front of the radical.
0 is the remainder, so we will have no y's left
under the radical. So we have:

But of course when the root is a square root,
we do not write the index, so we will drop the
index 2, and the 1 exponents as well:
Edwin
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Question 165240: I need to solve the equation for r:
w=Cr^-2: I need to solve the equation for r:
w=Cr^-2 Answer by vleith(1156) (Show Source): |
Question 165003: 25x^4-25^2+6=0
The solution is x=
The answer that I got is:
sqrt15/5,-sqrt15/5
is this correct!: 25x^4-25^2+6=0
The solution is x=
The answer that I got is:
sqrt15/5,-sqrt15/5
is this correct! Answer by edjones(2391) (Show Source): |
Question 165083This question is from textbook Elementary and Intermediate
: 30.) Solve each equation and check for extraneous solutions.
sqrt(a-1 -5 = 1)
This question is from textbook Elementary and Intermediate
: 30.) Solve each equation and check for extraneous solutions.
sqrt(a-1 -5 = 1)
Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website!I'm assuming that you mean  ??? Be careful to place your parenthesis in the right spot.
 Start with the given equation.
 Add 5 to both sides.
 Add.
 Square both sides to eliminate the square root.
 Square 6 to get 36.
 Add  to both sides.
 Combine like terms on the right side.
----------------------------------------------------------------------
Answer:
So the answer is
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Question 165061This question is from textbook Elementary and Intermediate
: 96.) Find all real or imaginary solutions. use the method of your choice.
sqrt(7x+29=x+3)
This question is from textbook Elementary and Intermediate
: 96.) Find all real or imaginary solutions. use the method of your choice.
sqrt(7x+29=x+3)
Answer by jim_thompson5910(9162) (Show Source):
You can put this solution on YOUR website! Start with the given equation
 Square both sides to eliminate the square root.
 FOIL the right side.
 Get everything to the right side.
 Combine like terms
Notice we have a quadratic equation in the form of  where  ,  , and
Let's use the quadratic formula to solve for x
 Start with the quadratic formula
 Plug in  ,  , and
 Negate  to get  .
 Square  to get  .
 Multiply  to get
 Rewrite  as
 Add  to  to get
 Multiply  and  to get  .
 Take the square root of  to get  .
 or  Break up the expression.
 or  Combine like terms.
 or  Simplify.
So the possible answers are  or
However, if you plug in  back into the original equation, you'll find that the solution does not work. So this means that  is NOT a solution.
===========================================
Answer:
So the solution is
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Question 165051: can someone help
. Multiply:
(sqrt[3] + 4sqrt[5])(2sqrt[3] – sqrt[5])
and
. Divide:
x2 – 3x + 2/8x - 8 ÷ x2 – 4/5x + 10
: can someone help
. Multiply:
(sqrt[3] + 4sqrt[5])(2sqrt[3] – sqrt[5])
and
. Divide:
x2 – 3x + 2/8x - 8 ÷ x2 – 4/5x + 10
Answer by nerdybill(1040) (Show Source):
You can put this solution on YOUR website!
(sqrt[3] + 4sqrt[5])(2sqrt[3] – sqrt[5])
Applying FOIL:
sqrt[3]2sqrt[3] - sqrt[3]sqrt[5] + 4sqrt[5]2sqrt[3] - 4sqrt[5]sqrt[5]
2(3) - sqrt[15] + 8sqrt[15] - 4(5)
6 - sqrt[15] + 8sqrt[15] - 20
6 + 7sqrt[15] - 20
7sqrt[15] - 14
OR, you could factor:
7(sqrt[15]-2)
.
Divide:
[(x2 – 3x + 2)/(8x - 8)] ÷ [(x2 – 4)/(5x + 10)]
Focusing on the first term in the [], we can factor:
[(x-2)(x-1)/8(x-1)] ÷ [(x2 – 4)/(5x + 10)]
Canceling like-terms:
[(x-2)/8] ÷ [(x2 – 4)/(5x + 10)]
.
Now, focus on the second term in the [], we can factor:
[(x-2)/8] ÷ [(x–2)(x+2)/5(x+2)]
Canceling like-terms:
[(x-2)/8] ÷ [(x–2)/5]
.
Now, we can change the divide to multiplication by flipping one of the terms:
[(x-2)/8] * [5/(x–2)]
Canceling like-terms:
[1/8] * [5/1]
Resulting in:
5/8
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Question 165005: subtract simply by collecting like radical terms it possible.
9 sqrt 18 - 6 sqrt 2: subtract simply by collecting like radical terms it possible.
9 sqrt 18 - 6 sqrt 2 Answer by nerdybill(1040) (Show Source): |
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