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tutorcecilia answered: 2042 problems
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Graphs/200573: Can you help me with this one?
-Plot the graphs of the following function.
Are you able to show me the graph for this one?

f(x)=(1/3)^x
1 solutions

Answer 150965 by tutorcecilia(2042) on 2009-06-21 01:12:28 (Show Source):

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I hope this helps.
tutorcecilia@yahoo.com

Polynomials-and-rational-expressions/200599: ADD or Subtract: x+6/ 5/4
2. 5/x - x-1/x
1 solutions

Answer 150964 by tutorcecilia(2042) on 2009-06-21 01:08:02 (Show Source):

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[since the denominators are the same, subtract the numerators]

Polynomials-and-rational-expressions/200672: m^4-n^4=
1 solutions

Answer 150963 by tutorcecilia(2042) on 2009-06-21 00:53:49 (Show Source):

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m^4-n^4 [factor the difference of two squares]
(m^2-n^2)(m^2+n^2)[again, factor the difference of two squares]
(m-n)(m+n)(m^2+n^2)

Rational-functions/200722: The American Bald Eagle weights about 12 pounds on average. Find using the rational exponent equation L=2.43*W^0.3326 to estimate the wingspan L in feet of the bird that weighs W pound. Please show work.
1 solutions

Answer 150961 by tutorcecilia(2042) on 2009-06-21 00:42:18 (Show Source):

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L=2.43*W^0.3326 [substitute the values wherever possible]
W=12
So,
L=2.43*(12)^0.3326
L=5.5532 feet
I hope this helps.
tutorcecilia@yahoo.com

Linear-equations/200724: I need to solve this linear equation, but i just do not know how. I need the proper steps to solving this problem. Please help!!!
3x-2.5y=7.125
2.5x-3y=7.3125
1 solutions

Answer 150960 by tutorcecilia(2042) on 2009-06-21 00:31:57 (Show Source):

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3x-2.5y=7.125
3x-3x-2.5y=-3x+7.125 [solve for "y" by isolating the y-variable]
-2.5y=-3x+7.125
-2.5y/-2.5=(-3x/-2.5) + (7.125/-2.5)
y=1.2x-2.85
.
2.5x-3y=7.3125
2.5x-2.5x-3y=-2.5x+7.3125
-3y=-2.5x+7.3125
-3y/-3=(-2.5x/-3)+(7.3125/-3)
y=0.8333x-2.4375

Expressions-with-variables/200349: The equation B=1+3n tells the number of beams required to build a frame of n sections. How many sections can be built with 79 beams?
1 solutions

Answer 150636 by tutorcecilia(2042) on 2009-06-16 21:20:02 (Show Source):

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B=1+3n
79=1+3n [substitute 79 for the B-variable]
79-1=1+3n [solve for the n-variable]
78=3n
78/3=3n/3
26 sections=n
Checking:
79=1+3(26)
79=79

Radicals/200252: what is the solution for square root of x6 over y5? thanks!
1 solutions

Answer 150634 by tutorcecilia(2042) on 2009-06-16 20:59:59 (Show Source):

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percentage/200284: This question is from textbook
An executive nearing retirement made two investments totaling $15,000. In one year, these investments yielded $1432 in simple interest. Part of the money was invested at 9% and the rest was invested at 10%. How much was invested at each rate?

1 solutions

Answer 150632 by tutorcecilia(2042) on 2009-06-16 20:39:45 (Show Source):

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x+y= $15,000
so, y=15,000-x
and
.09x+.10y=$1432
so,
.09x+.10(15,000-x)=1432
.09x+1500.-10x=1432
.09x+.10x=-1500+1432
-.01x=-68
-.01x/-.01=-68/-.01
x=6800
Subtracting:
15,000-6800=8,200
So, y=$8,200
Checking:
x+y=15,000
6,800+8,200=15,000
$6,800 was invested at 9%
$8,200 was invested at 10%

.
.

Trigonometry-basics/200332: how to solve 3x-2x+5
1 solutions

Answer 150629 by tutorcecilia(2042) on 2009-06-16 19:59:49 (Show Source):

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3x-2x+5 [combine like terms wherever possible]
x+5

test/200341: a^5times a^-8

1 solutions

Answer 150627 by tutorcecilia(2042) on 2009-06-16 19:55:01 (Show Source):

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a^(-3)
1/a^3

Miscellaneous_Word_Problems/199909: Venture capital. Henry invested $12,000 in a new
restaurant. When the restaurant was sold two years
later, he received $27,000. Find his average annual
return by solving the equation 12,000(1 + r)^2=
27,000.
1 solutions

Answer 150337 by tutorcecilia(2042) on 2009-06-13 18:00:35 (Show Source):

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I am assumeing that "r" is the average annual revenue, so I will solve for "r":
12,000(1 + r)^2=27,000
12,000/12,000(1+r)^2=27,000/12,000 [Isolate the r-variable]
(1 + r)^2=2.25
(sqrt(1+r)^2=sqrt(2.25)
1+r=1.5
r=1.5-1
r=0.5
Check by plugging 0.5 back into the original equation and solve.

Square-cubic-other-roots/199971: This question is from textbook Beginning Algebra
5 times sqrt of 24 + sqrt of 81 + 3 times sqrt of 18
combine without calculator or table of square roots

1 solutions

Answer 150336 by tutorcecilia(2042) on 2009-06-13 17:35:15 (Show Source):

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[Factor wherever possible to produce a square.
.

Equations/197670: Find the value of y in the equation

y=2x^2-x+5 if x =4

thank you
1 solutions

Answer 148225 by tutorcecilia(2042) on 2009-05-25 17:48:24 (Show Source):

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y=2x^2-x+5 if x =4
Plug-in "4" instead of "x" and solve the problem.
.
y=2(4)^2-(4)+5 Simplify using the order of operations (PEMDAS)
y=2(16)-4+5
y=32-4+5
y=28+5
y=33

Rational-functions/197390: State the domain of the following and provide a brief explanation for your answer: l(x) = 2x + 3
1 solutions

Answer 148221 by tutorcecilia(2042) on 2009-05-25 17:38:07 (Show Source):

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l(x) = 2x + 3
The domain is All Real Numbers because any real number can be plugged into the equation to make it true. Just try any real number for the "x".

Equations/197667: please divide

16m^3n^4

over

20mn^6

thank you
1 solutions

Answer 148220 by tutorcecilia(2042) on 2009-05-25 17:34:22 (Show Source):

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16m^3n^4/20mn^6
4m^(3-1)/5n^(6-4)
4m^2/5n^2

Distributive-associative-commutative-properties/197516: name the property used in the equation 11*n=1 and then solve

1 solutions

Answer 148141 by tutorcecilia(2042) on 2009-05-24 17:31:25 (Show Source):

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This is an example of the multiplicative inverse property. That means the term is multiplied by its inverse which is 1/11
.
So, 11*1/11 =1
When you multiply by the inverse the answer will be "1"

Complex_Numbers/194824: Find the product of the complex numbers.

Part 1: Use the FOIL method to find the product.
Part 2: Add any like terms from part 1 together and write your answer in the form a+bi. Show your work.
1 solutions

Answer 146171 by tutorcecilia(2042) on 2009-05-05 10:17:29 (Show Source):

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Distributive-associative-commutative-properties/194828: (7x-5)(3x+2)
1 solutions

Answer 146163 by tutorcecilia(2042) on 2009-05-05 07:38:04 (Show Source):

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(7x-5)(3x+2)
Use FOIL to solve: 21x^2+14x-15x-10
Combine like-terms: 21x^2-x-10

Linear-equations/178461: write the equation of a line parallel to x+2y=7.which passes through the point(-5,-4)
the answer I came up with was y=-1/2x-13/2 is this correct?
1 solutions

Answer 133407 by tutorcecilia(2042) on 2009-01-25 18:07:05 (Show Source):

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x+2y=7 Rewrite in the slope-intercept format to identify the slope
2y=-x+7
2/2y=-1/2x+7/2
y=-1/2x+7 Resulting in a slope of -1/2
.
y=mx+b Since the lines are parallel, the slopes of the two lines are equal
The second line has a slope of -1/2 and a point of (-5, -4)
-4=(-1/2)(-5) + b Plug-in the values in order to solvle for the y-intercept
-4=5/2+b Solve for the b-value (also known as the y-intercpet)
-4+(-5/2)=b
-13/2=b
.
Putting it all together gives your answer in which I agree:
y=-1/2x-13/2
.
Check by graphing both lines. They should have the same slope on your calculator.

Equations/177980: 3x8-4x(5-1)=3 Explain how the answer comes out to be 3
1 solutions

Answer 132963 by tutorcecilia(2042) on 2009-01-22 17:58:04 (Show Source):

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I don't think the answer is 3, you are suppose to solve for the x-value. Please re-check all of the numbers and variables and resubmit or send to me I will try to solve it for you at tutorcecilia@yahoo.com
Thanks.

Expressions-with-variables/176351: a(a-3)
1 solutions

Answer 131450 by tutorcecilia(2042) on 2009-01-13 09:32:20 (Show Source):

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Use the distributive property to multiply each term by "a"

expressions/175959: 20)4^-2
simplify
1 solutions

Answer 131067 by tutorcecilia(2042) on 2009-01-11 09:22:58 (Show Source):

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(

)
(

) Place 4^-2 in the denominator in order to get rid of the negative exponent
.
(

)
.
(

)Simplify

real-numbers/174657: How many significant digits are in 20.50?
1 solutions

Answer 129682 by tutorcecilia(2042) on 2008-12-31 12:27:04 (Show Source):

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There are only three significant digits. The last zero is just a "place holder" and has no value.
If the number were 20.05, than it would have four significan digits because the last zero is followed by a number (other than another zero).

Rational-functions/174651: perform the operation and reduce answer to the lowest term:
2 + 3
x-3 3-x
1 solutions

Answer 129665 by tutorcecilia(2042) on 2008-12-31 10:56:59 (Show Source):

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You may want to re-type this problem exactly as it is written in your text. I don't think it is written with the all of the correct symbols and operations. Thanks.

Human-and-algebraic-language/174591: This question is from textbook AMSCO`s Integrated Algebra 1
a small park is in the shape of a rectangle that measures 525 feet by 468 feet.
a.) find the number of feet of fencing that would be needed to enclose the park. Express your answer to the nearest foot.
1 solutions

Answer 129597 by tutorcecilia(2042) on 2008-12-30 14:04:08 (Show Source):

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Perimeter = 2(length + width) Use the formula for the perimeter of a rectangle]
P=2(525 + 468 feet) [Insert the known variables into the formula]
P=2(993) [simplify and solve]
Perimeter = 1986 feet

Expressions-with-variables/174575: reduce the expression to the lowest term:
4x^2
2x^9
1 solutions

Answer 129596 by tutorcecilia(2042) on 2008-12-30 12:51:14 (Show Source):

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Is this suppose to be a fraction? If so:
(

)
.
(

)

Exponents/174580: (x^2-2x-3=0)
1 solutions

Answer 129595 by tutorcecilia(2042) on 2008-12-30 12:45:53 (Show Source):

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x^2-2x-3=0
(x-3)(x+1)=0 [factor]
x-3=0 [set each factor equal to zero and solve for the x-value]
x=3
and
x+1=0
x=-1
So, the solutions are x = 3 and x = -1

percentage/174505: The sales price of a car is $12,590, which is 20% off the original price. What is the original price?
A. $14,310.40
B. $14,990.90
C. $15,290.70
D. $15,737.50
E. $16,935.80

1 solutions

Answer 129505 by tutorcecilia(2042) on 2008-12-28 14:35:30 (Show Source):

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x - .20x = 12,590 {Let x represent the unknown original amount; subtract 20% of the original (x) price]
.
.80x = 12,590 [Subtract the x-terms]
.
(

= (

[ Isolate the x-term through division]
.
x = $15,737.50 [Original price]

Exponents/174506: Solve the following equation for A : 2A/3 = 8 + 4A
A. -2.4
B. 2.4
C. 1.3
D. -1.3
E. 0

1 solutions

Answer 129504 by tutorcecilia(2042) on 2008-12-28 14:22:20 (Show Source):

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2A/3 = 8 + 4A
(3) (

) [eliminate the fraction by multiplying completely by "3"]
.
2A = 24 + 12A [Isolate the "A" term if possible]
.
2A - 12A = 24 [Simplify]
.
-10A = 24
.
(

)

.
A=-2.4

Inequalities/173405: A car traveled 715 km in 2 hours. What was it's average speed?
1 solutions

Answer 128267 by tutorcecilia(2042) on 2008-12-15 07:56:35 (Show Source):

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distance = (rate)(mph)
715=(rate)(2 hours)A car traveled 715 km in 2 hours
715/2=[(rate)(2 hours)]/2 Solve for the "rate"
357.5mph = rate

Quadratic_Equations/173412: This question is from textbook Introductory Algebra
Express radicals in simplest form.
x^2 + 3 = 52
1 solutions

Answer 128266 by tutorcecilia(2042) on 2008-12-15 07:45:36 (Show Source):

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= 52

= 52-52

= 0
(x-7)(x+7) Factor
x-7=0
x=7
and
x+7=0
x=-7
.
.
Solutions: x = 7 and x = -7