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checkley77 answered: 12560 problems
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(Please explain). 1 solutions
Answer 209545 by checkley77(12569) on 2010-04-06 15:41:03 (Show Source):
You can put this solution on YOUR website!y=(-1/2)x+4 (red line)
This line has a slope=-1/2.
Any perpendicular line will have a slope=the negative reciprocal of -1/2 OR 2.
y=2x+4 (green line)
 (graph 300x300 pixels, x from -10 to 10, y from -10 to 10, of TWO functions -x/2 +4 and 2x +4).
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Triangles/289188: How do you find a triangle whose ratio is 2:5:8 - this is sophmore advanced geometry and I am just a homebound teacher. please help!!! 1 solutions
Answer 209543 by checkley77(12569) on 2010-04-06 15:35:24 (Show Source):
You can put this solution on YOUR website!2:5:8
IF these are the ratios of the three sides.
2n+5n+8n=15n where n is the multiplier of the sides..
However; these ratios are not valid for a triangle.
The sum of the 2 smallest sides (2+5)=7 is less than the third side=8.
Thus these ratios cannot be used to make a triangle.
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IF these ratios are for the angles then:
2n+5n+8n=15n
15n=180
n=180/15
n=12 is the multiplier of the ratio values.
2*12=24 degrees.
5*12=60 degrees.
8*12=96 degrees.
Proof:
24+60+96=180
180=180
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Linear-equations/289053: Please help me solve this equation:
Write the equation of the line passing through each of the given pairs of points. Write your result in slope-intercept form, where possible.
(-4, 1) and (3, 1)
1 solutions
Answer 209408 by checkley77(12569) on 2010-04-06 09:03:44 (Show Source):
You can put this solution on YOUR website!(-4, 1) and (3, 1)
Slope=(y2-y1)/(x2-x1)
Slope=(1-1)/(3+4)=0/7 this indicates an horizontal line through y=1
Thus the line equation is:
Y=1
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = 1).
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Finance/288784: Determine the amount of an investment if $15,000 is invested at an iterest of 4.85% compound quarterly for 5 years 1 solutions
Answer 209286 by checkley77(12569) on 2010-04-05 17:54:59 (Show Source):
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Money_Word_Problems/288702: Susan works in a large department store and earns $6.00 per hour. The store will pay her an extra 5% in salary for each hour that she sells more than $100 worth of merchandise. She makes this sales quote for each hour of her 4-hour shift. How much will she earn for the shift? 1 solutions
Answer 209280 by checkley77(12569) on 2010-04-05 17:43:55 (Show Source):
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Permutations/288705: suppose they are 10 questions on a true false test. what is the probability the person will get all answers correct. without reading them. thank you for the help 1 solutions
Answer 209277 by checkley77(12569) on 2010-04-05 17:27:17 (Show Source):
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Polynomials-and-rational-expressions/288709: My issue if finding a LCM to this equation. My teacher didn't explain it very well, however, I think AFTER obtaining the LCM I understand how to solve the equation. This particular problem is:
7/(x-3) - (2/7) = -10/(3x-9) 1 solutions
Answer 209275 by checkley77(12569) on 2010-04-05 17:19:17 (Show Source):
You can put this solution on YOUR website!7/(x-3) - (2/7) = -10/(3x-9)
[7*7-2(x-3)]/7(x-3)=-10/(3x-9)
[49-2x+6]/(7x-21)=-10/(3x-9)
[-2x+55]/(7x-21)=-10/(3x-9) cross multiply.
-10(7x-21)=(3x-9)(-2x+55)
-70x+210=-6x^2+18x+165x-495
-70x+210=-6x^2+183x-495
6x^2-70x-183x+210+495=0
6x^2-253x+705=0
(6X-235)(X-3)=0
6X-235=0
6X=235
X=235/6 ANS.
X-3=0
X=3 ANS.
PROOF:
7/(x-3) - (2/7) = -10/(3x-9)
7/[(235/6)-3]-2/7=-10/[(3*235/6)-9]
7/[(235-3*6)/6]-2/7=-10/[(705/6)-9]
7/[217/6]-2/7=-10/[705-9*6]/6
7*6/217-2/7=-10/[705-54]/6
42/217-2/7=-10/[651]/6
.1935-.2857=-10*6/651
-.0922=-60/651
-.0922=-.0922
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Numeric_Fractions/288715: at baxter high school, two-fifth of the students are taking language classes. one-fourth of those students are studying french. what percent of the students at baxter high are studying french? 1 solutions
Answer 209267 by checkley77(12569) on 2010-04-05 16:29:02 (Show Source):
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Rectangles/288741: length of a rectangle is 8 in less than twice the width. the area is 90 in squared find the width 1 solutions
Answer 209263 by checkley77(12569) on 2010-04-05 16:19:12 (Show Source):
You can put this solution on YOUR website!L=2W-8
AREA=LW
90=(2W-8)W
90=2W^2-8W
2W^2-8W-90=0
2(W^2-4W-45)=0
2(W-9)(W+5)=0
W-9=0
W=9 ANS. FOR THE WIDTH.
L=2*9-8
L=18-8
L=10 ANS. FOR THE LENGTH.
PROOF:
90=10*9
90=90
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Quadratic_Equations/288753: A total of 1135 people attended a concert. Floor tickets cost $40 each, while balcony tickets cost $28 each. If a total of $40,480 was collected, how many of each type of ticket were sold? 1 solutions
Answer 209258 by checkley77(12569) on 2010-04-05 16:05:07 (Show Source):
You can put this solution on YOUR website!F+B=1,135 OR F=1,135-B
40F+28B=40,480
40(1,135-B)+28B=40,480
45,400-40B+28B=40,480
-12B=40,480-45,400
-12B=-4,920
B=-4,920/-12
B=410 NUMBER OF BALCONY TICKETS WERE SOLD.
1,135-410=725 NUMBER OF FLOOR TICKETS WERE SOLD.
40*725+28*410=40,480
29,000+11,480=40,480
40,480=40,480
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Quadratic_Equations/288724: A picture that measures 10cm by 8cm is to be surrounded by a mat before framing. The width of the mat is to be the same on all sides of the picture. The area of the mat is equal to the area of the picture. What is the width of the mat, to the nearest tenth of a centimetre? 1 solutions
Answer 209255 by checkley77(12569) on 2010-04-05 15:42:17 (Show Source):
You can put this solution on YOUR website!10*8=80 cm^2 is the area of the picture.
(10+2x)(8+2x)-80=80
80+16x+20x+4x^2-160=0
4x^2+36x-80=0
4(x^2+9x-20)=0

x=(-9+-sqrt[9^2-4*1*-20])/2*1
x=(-9+-sqrt[81+80])/2
x=(-9+-sqrt161)/2
x=(-9+-12.69)/2
x=(-9+-12.69)/2
x=(-9+12.69)/2
x=3.69/2
x=1.8 cm. is the width of the mat.
Proof:
(10+2*1.8)(8+2*1.8)-80=80
(10+3.6)(8+3.6)=160
13.8*11.6=160
160~160
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Equations/288736: How much of a 10% saline solution should be mixed with a 20% saline solution to obtain 1000 milliters of a 12% saline solution?
Use a system of equations and substitution to solve each problem.
Thanks 1 solutions
Answer 209244 by checkley77(12569) on 2010-04-05 15:19:02 (Show Source):
You can put this solution on YOUR website!A single equation is a much simplier method.
.20x+.10(1,000-x)=.12*1,000
.20x+100-.10x=120
.10x=120-100
.10x=20
x=20/.10
x=$200 invested @ 20%.
1,000-200=$800 invested @ 10%.
Proof:
.20*200+.10*800=.12*1,000
40+80=120
120=120
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Linear-systems/288434: juan made 2L of lemonade that consists of 40% pure lemon juice. how much water must he add to dilute it to 30% lemon juice 1 solutions
Answer 209077 by checkley77(12569) on 2010-04-04 18:41:10 (Show Source):
You can put this solution on YOUR website!2*.40=(2+x).30
.80=.60+.30x
.30x=.80-.60
.30x=.20
x=.20/.30
x=2/3 of a liter of water is needed.
Proof:
2*.40=(2+2/3).30
.8=8/3*.30
.8=2.4/3
.8=.8
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Rectangles/288260: A rectangle has a diagonal that measures 10 centimeters and a length that is 2 centimeters longer than the width.What is the width of the rectangle in centimeters? 1 solutions
Answer 209076 by checkley77(12569) on 2010-04-04 18:35:31 (Show Source):
You can put this solution on YOUR website!a^2+b^2=c^2
a^2+(a+2)^2=10^2
a^2+a^2+4a+4=100
2a^2+4a+4-100=0
2a^2+4a-96=0
2(a^2+2a-48)=0
2(a+8)(a-6)=0
a-6=0
a=6 cm. ans. for the short side.
6+2=8 cm. ans. for the long side.
Proof:
6^2+8^2=100
36+64=100
100=100
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Rectangles/288262: A rectangle has a diagonal that measures 10 centimeters and a length that is 2 centimeters longer than the width.What is the width of the rectangle in centimeters? 1 solutions
Answer 209074 by checkley77(12569) on 2010-04-04 18:25:23 (Show Source):
You can put this solution on YOUR website!a^2+b^2=c^2
a^2+(a+2)^2=10^2
a^2+a^2+4a+4=100
2a^2+4a+4-100=0
2a^2+4a-96=0
2(a^2+2a-48)=0
2(a+8)(a-6)=0
a-6=0
a=6 cm. ans. for the short side.
6+2=8 cm. ans. for the long side.
Proof:
6^2+8^2=100
36+64=100
100=100
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Bodies-in-space/288267: If there are 7.5 gallons to the cubic foot, and a cylindrical storage tank has a radius of 21 ft and an altitude of 28 ft, then using 3.14159 for π ,how many gallons, correct to the nearest whole gallon, will the full storage tank hold? 1 solutions
Answer 209072 by checkley77(12569) on 2010-04-04 18:19:23 (Show Source):
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