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checkley77 answered: 12560 problems
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decimal-numbers/263547: Express the decimal number 4693 as a binary number?
1 solutions

Answer 194212 by checkley77(12569) About Me  on 2010-01-31 17:48:53 (Show Source):
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4693=1001001010101
OR
4096
&512
&&64
&&16
&&&4
&&&1
------
4693


Square-cubic-other-roots/263552: solve by completing the square: x^2 + 5x -8=0
1 solutions

Answer 194206 by checkley77(12569) About Me  on 2010-01-31 17:40:30 (Show Source):
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x^2 + 5x -8=0
X^2+5X+25/4=8+25/4
(X+5/2)^2=(4*8+25)/4
(X+5/2)^2=(32+25)/4
(X+5/2)^2=57/4 ANS.


Miscellaneous_Word_Problems/263555: the owner of an apple orchard ships apples in boxes that weigh 2 kilograms when empty.the average apple weighs 0.25 kilograms and the total weight of a box filled with apples is 12 kilograms. How many appls are packed in each box?
1 solutions

Answer 194203 by checkley77(12569) About Me  on 2010-01-31 17:36:03 (Show Source):
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2+.25X=12
.25X=12-2
.25X=10
X=10/.25
X=40 APPLES PER BOX.
PROOF:
2+.25*40=12
2+10=12
12=12


Proportions/263556: 8=X/3-8
I KNOW U ADD 8 FROM BOTH SIDES BUT THEN WHAT
1 solutions

Answer 194202 by checkley77(12569) About Me  on 2010-01-31 17:33:48 (Show Source):
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8=X/3-8 ADD 8
16=X/3 CROSS MULTIPLY
X=16*3
X=48 ANS.
PROOF:
8=48/3-8
8=16-8
8=8


percentage/263549: here is the qusetion The pie chart below represents the number of students enrolled at each course at Lakeside High School. Using this information, find the percentage of students enrolled in History. Round your answer to the nearest tenth of a percent.
Math:57
History:117
English:93
Chemistry:36
1 solutions

Answer 194201 by checkley77(12569) About Me  on 2010-01-31 17:31:00 (Show Source):
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Math:57
History:117
English:93
Chemistry:36
TOTAL=57+117+93+36=303 STUDENTS.
117/303=.386=38.6 % OF THE STUDENTS WERE ENROLLED IN HISTORY.


Linear_Equations_And_Systems_Word_Problems/263443: In 1996 there were 3927 J.C. Penney stores and in 2000 there were 3800 stores. Write a linear equation that gives the number of stores in terms of the year. Let t=0 represent 1996. Then predict the numbers of stores for the years 2005 and 2010.
1 solutions

Answer 194199 by checkley77(12569) About Me  on 2010-01-31 17:25:34 (Show Source):
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Y=mX+b WHERE m=SLOPE & b=THE Y INTERCEPT.
USING THE POINTS (0,3927) & (4,3800)
SLOPE=(3800-3927)/(4-0)
SLOPE=-127/4
SLOPE=-31.75
3927=-31.75*0+b
3927=b
b=3927
Y=mX+b
Y(9)=-31.75*0+3927
Y=-31.75X+3927
Y=-31.45*9+3927
Y=-285.75+3927
Y=3641.25 STORES IN 2005.
Y(14)=-31.75*14+3927
Y=-444.50+3927
Y=3482.5 STORES IN 2010


Money_Word_Problems/263445: An employee who produces x units per hour earns an hourly wage of y=0.95x + 7 (in dollars). Find the hourly wage for an employee who produces 6 units per hour.
Answers:
A). $13.20
B). $12.40
c). $13.10
d). $12.70

1 solutions

Answer 194188 by checkley77(12569) About Me  on 2010-01-31 16:30:59 (Show Source):
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y=0.95x + 7 WHEN X=6:
Y=.95*6+7
Y=5.70+7
Y=$12.70 IS THE HOURLY WAGE.
ANSWER D)


Unit_Conversion_Word_Problems/263446: An auto has a gas mileage of 25.6 mi/gallon. How many kilometers can it travel on 1.5 L of gas?
1.61 km= 1 mile
3.79L= 1 gallon
I have tried this several ways..i have no idea. I divided 25.6 by 1.61 and got 15.9 km. Then i multiplied 15.9km by 1.5L and divided by 3.79L.....no clue
1 solutions

Answer 194187 by checkley77(12569) About Me  on 2010-01-31 16:26:44 (Show Source):
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25.6*1.61=41.216 KM. PER GAL.
(41.216/3.79)=10.875 KM PER LITEER.
10.875*1.5=16.31 KM ON 1.5 LITERS OF GAS.


Polynomials-and-rational-expressions/263460: Add, simplify by collecting like radical terms if possible, assuming that all expressions under radicals represent nonnegative numbers. (sqrt10a) + (2sqrt250a^3)
1 solutions

Answer 194179 by checkley77(12569) About Me  on 2010-01-31 16:07:55 (Show Source):
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(sqrt10a) + (2sqrt250a^3)
SQRT10A+2*5A^2SQRT10A
5SQRT10A+10A^2SQRT10A
(5+10A^2)(SQRT10A)
5(1+2A^2)(SQRT10A)


Probability-and-statistics/263461: An automobile manufacturer produces 7 models, each available in 6 different exterior colors, with 4 different upholstery fabrics and 5 interior
colors. How many varieties of automobile are available?
1 solutions

Answer 194177 by checkley77(12569) About Me  on 2010-01-31 16:03:35 (Show Source):
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7*6*4*5=840 POSSIBLE VARIETIES OF CARS ARE AVAILABLE.


Mixture_Word_Problems/263463: Find the cost per ounce of a sunscreen made from 130 oz of lotion that cost $3.41 per ounce and 90 oz of lotion that cost $11.99 per ounce.
1 solutions

Answer 194174 by checkley77(12569) About Me  on 2010-01-31 16:01:01 (Show Source):
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3.41*130+11.99*90=220X
443.30+1,079.10=220X
1,522.4=220X
X=1,522.4/220
X=$6.92 COST OF THE MIXTURE PER OZ.
PROOF:
3.41*130+11.99*90=220*6.92
443.30+1,079.10=1,522.40
1,522.40=1,522.40


Linear_Equations_And_Systems_Word_Problems/263464: Write the equation of a line with the slope of -2 which contains the point (3,6)

1 solutions

Answer 194172 by checkley77(12569) About Me  on 2010-01-31 15:55:46 (Show Source):
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slope=-2 through (3,6)
Y=mX+b
6=-2*3+b
6=-6+b
b=6+6
b=12 the Y intercept.
Y=-2x+12 is the line equation.
+graph%28+300%2C+200%2C+-6%2C+10%2C+-10%2C+15%2C+-2x+%2B12%29+ (graph 300x200 pixels, x from -6 to 10, y from -10 to 15, -2x +12).


Graphs/263466: Solve this equation 3x -9 =3y
1 solutions

Answer 194169 by checkley77(12569) About Me  on 2010-01-31 15:51:19 (Show Source):
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3x -9 =3y
3Y=3X-9
Y=3X/3-9/3
Y=X-3
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+x+-3%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, x -3).


Rectangles/263469: The length of a rectangular board is 9 meters greater than the width. If the perimeter of the board is 26 meters, then what are the length and the width?
1 solutions

Answer 194167 by checkley77(12569) About Me  on 2010-01-31 15:46:55 (Show Source):
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L=W+9
2L+2W=26
2(W+9)+2W=26
2W+18+2W=26
4W=26-18
4W=8
W=8/4
W=2 ANS. FOR THE WIDTH.
L=2+9=11 ANS. FOR THE LENGTH.
PROOF:
2*11+2*2=26
22+4=26
26=26


Linear-systems/263475: Can you help me find the point slope form of this equation? (6,2) and m= 1/2
Thanks!
1 solutions

Answer 194166 by checkley77(12569) About Me  on 2010-01-31 15:43:46 (Show Source):
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(6,2) and m= 1/2
Y=mX+b where m=slope & b=the Y intercept.
2=6/2+b
2=3+b
b=2-3
b=-1 the Y intercept.
Y=X/2-1 is the line equation.
+graph%28+300%2C+200%2C+-6%2C+8%2C+-10%2C+10%2C+x%2F2+-1%29+ (graph 300x200 pixels, x from -6 to 8, y from -10 to 10, x/2 -1).


Linear-systems/263478: How would you graph this? -x -y =3
1 solutions

Answer 194163 by checkley77(12569) About Me  on 2010-01-31 15:37:53 (Show Source):
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-x -y =3
-Y=X+3
Y=-X-3 THE Y INTERCEPT=(0,-3)
SETTING Y=0 & SOLVE FOR X WE GET:
0=-X-3
X=-3 THE X INTERCEPT=(-3,0)
PLOT THESE 2 INTERCEPTS & DRAW THE LINE BETWEEN THEM.
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+-x+-3%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, -x -3).


Word_Problems_With_Coins/263481: a coin bank containe nickels, dimes, and quarters totaling $5.45. If there are twice as many quarters as dimes and 11 more nickels than quarters, how many of each coin are in the bank?
1 solutions

Answer 194160 by checkley77(12569) About Me  on 2010-01-31 15:33:51 (Show Source):
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Q=2D OR D=Q/2
N=Q+11
N+D+Q=5.45
.05N+.10D+.25Q=5.45
.05(Q+11)+.10(Q/2)+.25Q=5.45
.05Q+.55+.05Q+.25Q=5.45
.35Q=5.45-.55
.35Q=4.90
Q=4.90/.35
Q=14 QUARTERS.
N=14+11=25 NICKELS
D=14/2=7 DIMES
PROOF:
.05*25+.10*7+.25*14=5.45
1.25+.70+3.50=5.45
5.45=5.45


Radicals/263477: Hi there! I am lost on this! Thank you!
Determine whether the triple of numbers can be the sides of a right triangle.


9, 12, 16

A)

Yes

B)

No
1 solutions

Answer 194158 by checkley77(12569) About Me  on 2010-01-31 15:25:29 (Show Source):
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9, 12, 16
A^2+B^2=C^2
9^2+12^2=16^2
81+144=256
225=256 DOES NOT IDENTIFY A RIGHT TRIANGLE.
ANSWER IS B) NO!
9^2+12^2=15^2
81+144=225
225=225 IS A RIGHT TRIANGLE.


Polynomials-and-rational-expressions/263473: Multiply and simplify by factoring. Assume that all expressions under radicals represent non negative numbers. (^3sqrt r^13)(^3sqrt16y^14)
1 solutions

Answer 194156 by checkley77(12569) About Me  on 2010-01-31 15:20:33 (Show Source):
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Is there supposed to be a value or unknown before the [^3] signs?
(^3sqrt r^13)(^3sqrt16y^14)


Expressions-with-variables/263342: Solve by the elimination method. 2x - 4y = 3
2x - 4y = 4
What is the solution of the system?
1 solutions

Answer 194063 by checkley77(12569) About Me  on 2010-01-31 10:12:09 (Show Source):
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2x - 4y = 3
2x - 4y = 4 subtract.
------------------------
0x+0y=-1 no unique solution for x or y.


Linear-systems/262921: 2x-y=6
3x+4y=-2
1 solutions

Answer 193924 by checkley77(12569) About Me  on 2010-01-30 19:14:54 (Show Source):
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2x-y=6 solve for y
y=2x-6
3x+4y=-2 replace y with (2x-6) & solve for x.
3x+4(2x-6)=-2
3x+8x-24=-2
11x=-2+24
11x=22
x=22/11
x=2 ANS.
y=2*2-6 substitute 2 for x & solve for y.
y=4-6
y=-2 ans.
Proof:
3*2+4*-2=-2
6-8=-2
-2=-2


Evaluation_Word_Problems/262944: Solve for x:
4 (x+2)+1= 7x - 3(x-2)
1 solutions

Answer 193920 by checkley77(12569) About Me  on 2010-01-30 19:07:55 (Show Source):
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4(x+2)+1=7x-3(x-2)
4x+8+1=7x-3x+6
4x-7x+3x=6-8-1
0x=-3 no solution for x.


Rational-functions/263004: f(x)=-x^2-2x+7
find the vertex and axis of symmetry and graph the function
1 solutions

Answer 193916 by checkley77(12569) About Me  on 2010-01-30 19:04:31 (Show Source):
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f(x)=-x^2-2x+7
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+-x%5E2+-2x+%2B7%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions -x^2 -2x +7).
Vertex=(-1,8)
Axis=-1


Human-and-algebraic-language/263055: triple a number minus the sum of the number and nine
1 solutions

Answer 193908 by checkley77(12569) About Me  on 2010-01-30 18:47:43 (Show Source):
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3X-(X+9) ANS.


Numeric_Fractions/263060: 5 3/16-9/16
1 solutions

Answer 193906 by checkley77(12569) About Me  on 2010-01-30 18:45:54 (Show Source):
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5 3/16-9/16
83/16-9/16
74/16=37/8 ans.


Travel_Word_Problems/263065: Find the x- and y-intercepts (if any) for each line. Show your work.
Plot those intercepts, and graph the two lines on the same chart. Submit your graph through the Dropbox.
Apply elimination or substitution to find the coordinates of the point of intersection (if there are no solutions or infinite solutions, state this). Show your work.
The 2 equations are:
x + 5y = 29
-7x + 4y = 70
Below is what I came up with but I just want to know if I did this correctly.
x + 5y = 29
y = 0 x + 5(0) = 29
x = 29
x = 0 0 + 5y = 29
5y = 29
y = 29/5
-7x + 4y = 70
y = 0 -7x + 4(0)= 70
-7x = 70
x = -10
x = 0 -7(0) + 4y = 70
4y = 70
y = 70/4 = 35/2

I will use the substitution system to point of intersection.
x = 29 - 5y
-7(29 - 5y) + 4y = 70
-203 + 35y + 4y = 70
39y = 273
y = 7
x + 5(7) = 29
x + 35 = 29
x = 29/35
1 solutions

Answer 193903 by checkley77(12569) About Me  on 2010-01-30 18:43:23 (Show Source):
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The 2 equations are:
x + 5y = 29
-7x + 4y = 70
Below is what I came up with but I just want to know if I did this correctly.
x + 5y = 29
y = 0 x + 5(0) = 29
x = 29
x = 0 0 + 5y = 29
5y = 29
y = 29/5
-7x + 4y = 70
y = 0 -7x + 4(0)= 70
-7x = 70
x = -10
x = 0 -7(0) + 4y = 70
4y = 70
y = 70/4 = 35/2
I will use the substitution system to point of intersection.
x = 29 - 5y
-7(29 - 5y) + 4y = 70
-203 + 35y + 4y = 70
39y = 273
y = 7
x + 5(7) = 29
x + 35 = 29
x = 29/35 GOOD WORK UP TO THIS POINT [X=29-35=-6 ans.]
Check the graph below.
+graph%28+300%2C+200%2C+-8%2C+5%2C+-10%2C+10%2C+-x%2F5+%2B29%2F5+%2C+7x%2F4+%2B35%2F2%29+ (graph 300x200 pixels, x from -8 to 5, y from -10 to 10, of TWO functions -x/5 +29/5 and 7x/4 +35/2).


Systems-of-equations/263067: SOLVE
-13<=4X-6<=-5
1 solutions

Answer 193882 by checkley77(12569) About Me  on 2010-01-30 17:53:57 (Show Source):
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-13<=4X-6<=-5
-13+6<=4X<=-5+6
-7<=4X<=1
-7/4<=X<=1/4 ans.


Travel_Word_Problems/263127: The speed of a stream is 4 mph. A boat travels 7 miles upstream in the same time it takes to travel 15 miles downstream. What is the speed of the boat in still water?

1 solutions

Answer 193881 by checkley77(12569) About Me  on 2010-01-30 17:51:28 (Show Source):
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D=RT OR T=D/R
TU=7/(R-C) TRAVEL UPSTREAM
TD=15/(R+C) TRAVEL DOWN STREAM.
THE TIMES ARE EQUAL.
7/(R-4)=15/(R+4) CROSS MULTIPLY.
15(R-4)=7(R+4)
15R-60=7R+28
15R-7R=28+60
8R=88
R=88/8
R=11 IS THE SPEED OF THE BOAT IN STILL WATER.
PROOF:
7/(11-4)=15(11+4)
7/7=15/15
1=1


Divisibility_and_Prime_Numbers/263129: how do you do factor form like
n to the second power + 11n +18
1 solutions

Answer 193874 by checkley77(12569) About Me  on 2010-01-30 17:43:15 (Show Source):
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n^2 + 11n +18
The factors of 18 are:
1 & 18 the sum=19
-1 & -18 the sum is=-19
2 & 9 the sum is=11 [the only factors that match the middle term.]
-2 & -9 the sum is=-11
3 & 6 the sium is=9
-3 & -6 the sum is=-9
(n+2)(n+9) ans.


Money_Word_Problems/262868: A bus driver wants to earn $3,500 per year in supplemental income from an inheritance of $40,000. If the driver invests $10,000 in a mutual fund paying 8%, what rate must he earn on the remainder to achieve his goal?
1 solutions

Answer 193673 by checkley77(12569) About Me  on 2010-01-29 21:25:46 (Show Source):
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.08*10,000+X*30,000=3,500
800+30,000X=3,500
30,000X=3,500-800
30,000X=2,700
X=2,700/30,000
X=.09 OR 9% IS THE RATE REQUIRED FOR THE $30,000 INVESTMENT TO MEET HIS GOALS.
PROOF:
.08*10,000+.09*30,000=3,500
800+2,700=3,500
3,500=3,500


Travel_Word_Problems/262869: Two truck drivers leave a warehouse traveling in opposite directions, one driving at 50 mph and one driving at 56 mph. If the slower driver has a 2-hour head start, how long has she been on the road when two drivers are 683 miles apart?
1 solutions

Answer 193669 by checkley77(12569) About Me  on 2010-01-29 21:16:08 (Show Source):
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D=RT
683=50T+65(T-2)
683=50T+65T-130
115T=683+130
115T=813
T=813/115
T=7.7 HOURS THE 50MPH CAR HAS BEEN ON THE ROAD WHEN THEY ARE 583 MILES APART.