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Coordinate-system/229381: when you have 2 sets of numbers, how do you know which set is for the up/down and which is left/rt
1 solutions

Answer 170140 by rfer(12730) About Me  on 2009-10-21 00:00:02 (Show Source):
You can put this solution on YOUR website!
x axis is horizontal
y axis is vertical
in an ordered pair the first number is always the x axis
the second is always the y axis
(x,y)


Quadratic-relations-and-conic-sections/229396: i am trying to find the y coordinate of the vertex. the x is -2 and when i plug it in to the equation i get
3(-2)^2+12(-2)+8 =-28, but the answer is supposed to be -4 can someone tell me what i am doing wrong?
1 solutions

Answer 170137 by rfer(12730) About Me  on 2009-10-20 23:52:18 (Show Source):
You can put this solution on YOUR website!
I think you lost track of a sign some where.
3(-2)^2+12(-2)+8=
3(+4)-24+8=
12-24+8=
20-24=-4


Distributive-associative-commutative-properties/229488: My problem is 14(1002)
1 solutions

Answer 170133 by rfer(12730) About Me  on 2009-10-20 23:44:27 (Show Source):
You can put this solution on YOUR website!
14(1002)
same as
14*1002=14028


Age_Word_Problems/229505: Could you please help jessica is twice as old as tina. In nine years the sum of their ages will be 66 how old is each today?here's what I have so far... Tina equals t while jessica equals 2t...(T+9)+(2t+9)equals 66
1 solutions

Answer 170131 by rfer(12730) About Me  on 2009-10-20 23:41:29 (Show Source):
You can put this solution on YOUR website!
t+9+2t+9=66
3t+18=66
3t=48
t=16
2t=32
your equation works
Good luck
Bob


Numbers_Word_Problems/229494: i need help with this problem
Ken is thinking of a number,Nine more than the product of 4 and the number
is 73. Find Kens number
1 solutions

Answer 170128 by rfer(12730) About Me  on 2009-10-20 23:36:59 (Show Source):
You can put this solution on YOUR website!
4x+9=73
4x=64
x=16


Exponents/229500: if y=3 then y3(y3-y)=
1 solutions

Answer 170127 by rfer(12730) About Me  on 2009-10-20 23:33:53 (Show Source):
You can put this solution on YOUR website!
y^3(y^3-y)=
3^3(3^3-3)=
27(24)=648


Travel_Word_Problems/229383: Katherine drove 230 miles. She drove 40mph for the first 2 hours and 50mhp for the rest of her drive. How long did she drive at 50mhp?
1 solutions

Answer 170077 by rfer(12730) About Me  on 2009-10-20 19:51:53 (Show Source):
You can put this solution on YOUR website!
230-80=150/50=3 hrs


Geometry_Word_Problems/229391: A farmer has 2400 feet of fencing and wants to enclose a rectangular area. What is the maximum area?
(do not type in units)

1 solutions

Answer 170074 by rfer(12730) About Me  on 2009-10-20 19:49:13 (Show Source):
You can put this solution on YOUR website!
a square is max
sq rt of 2400=49
49*49=2400


Travel_Word_Problems/229388: I really need help. I'm just not getting this at all. Can someone please help?
Two cars are traveling in the same direction. The first car is going 45 mi/h and the second car is going 60 mi/h. The first car left 2 hours before the second car. Explain how you could solve an equation with variables on both sides to find how long it will take the second car to catch up to the first.
1 solutions

Answer 170073 by rfer(12730) About Me  on 2009-10-20 19:47:02 (Show Source):
You can put this solution on YOUR website!
car A is two hours ahead or 90 miles.
overtake speed is 60-45=15 mph.
90/15=6 hrs to catch up.
2(45)/(60-45)=x


Linear-equations/229195: Find the x and y intercept points of -3x-2y=12
1 solutions

Answer 170026 by rfer(12730) About Me  on 2009-10-20 17:37:10 (Show Source):
You can put this solution on YOUR website!
y int x=0 (0,-6)
x int y=0 (-4,0)
-3x-2y=12
-2y=3x+12
2y=-3x-12
y=(-3x-12)/2
y=-3(0)-12/2
y=-6
(0,-6)
---------------------
-3x=2y+12
3x=-2y-12
x=(-2y-12)/3
x=-2(0)-12/3
x=-4
(-4,0)


Problems-with-consecutive-odd-even-integers/229258: An angle (a) measures 20 degrees more than the measure of its complement. Find the angle's supplement. [Hint: what symbol do you use for the word "measures"????]
1 solutions

Answer 170024 by rfer(12730) About Me  on 2009-10-20 17:30:00 (Show Source):
You can put this solution on YOUR website!
x+x+20=90
2x=70
x=35 degrees
x+20=55 degrees
-----------------
180-55=125 degrees


Miscellaneous_Word_Problems/229219: When 30% of a number is added to the number, the result is 54.6. What is the number?
1 solutions

Answer 170022 by rfer(12730) About Me  on 2009-10-20 17:25:11 (Show Source):
You can put this solution on YOUR website!
x+.3x=54.3
1.3x=54.3
x=41.77


Graphs/229265: How do you get an equation for a parallel line that passes through a given point?
example: (3,4); y=2x-7
1 solutions

Answer 170016 by rfer(12730) About Me  on 2009-10-20 17:18:47 (Show Source):
You can put this solution on YOUR website!
Plot the point and use the same slope as the first equation.
It becomes
y=2x-2


Linear-equations/229277: what is(1,-5),m-3/2
1 solutions

Answer 170012 by rfer(12730) About Me  on 2009-10-20 17:13:23 (Show Source):
You can put this solution on YOUR website!
y=mx+b
y=-3/2x-3.5


Trigonometry-basics/229280: solve the following equation for the given value of x:
y= cos x; for x = 4 pie
1 solutions

Answer 170010 by rfer(12730) About Me  on 2009-10-20 17:11:11 (Show Source):
You can put this solution on YOUR website!
y=cos x
y=cos(4*3.14)
y=cos 12.56
y=0.976


Numbers_Word_Problems/229208: Of two numbers , one exceeds the other by 32. their sum is 46 . find the numbers.
1 solutions

Answer 170007 by rfer(12730) About Me  on 2009-10-20 17:07:33 (Show Source):
You can put this solution on YOUR website!
x+x+32=46
2x=14
x=7
x+32=39


Surface-area/229263: A trapezoid has three sides of length 4 inches and one side of length 8 inches. What is its area?
1 solutions

Answer 170006 by rfer(12730) About Me  on 2009-10-20 17:02:54 (Show Source):
You can put this solution on YOUR website!
find the heigth
16-4=12
sq rt of 12=3.46
------------------
A=h((b1+b2)/2)
A=3.46(12/2)
A=3.46*6
A=20.76 sq in


Miscellaneous_Word_Problems/229240: carry out the indicated operation and give your answer with 2 significant digits 274.23/.087. What is 274.23/.087 with two significant digits? answer in integer or decimal
1 solutions

Answer 170000 by rfer(12730) About Me  on 2009-10-20 16:52:46 (Show Source):
You can put this solution on YOUR website!
274.23/.087=3152.07


Linear_Equations_And_Systems_Word_Problems/228950: Bill travels 8mph and Karen 3mph. They live 8.25 miles apart. How long will it take before they meet?
1 solutions

Answer 169900 by rfer(12730) About Me  on 2009-10-19 22:41:40 (Show Source):
You can put this solution on YOUR website!
8.25/11=3/4 hr=45 min


Linear-equations/229039: I need help with the Linear Equations Clearing Fractions. My question is:
(4z+7)/5 = z+2
I can usually get the ones I miss if I leave it alone for a few minutes and go back to it but this one is just not working for me.
Thank YOU Very Much,
belovedwon@comcast.net

1 solutions

Answer 169897 by rfer(12730) About Me  on 2009-10-19 22:36:13 (Show Source):
You can put this solution on YOUR website!
(4z+7)/5=z+2
multiply by 5
4z+7=(z+2)5
4z+7=5z+10
subtract 4z
7=z+10
subtract 10
z=-3


expressions/229006: Simplify: -6[39 -(-88 -8)]
1 solutions

Answer 169874 by rfer(12730) About Me  on 2009-10-19 21:49:38 (Show Source):
You can put this solution on YOUR website!
-6(39-(-88-8))
-6(39+96)
-6(135)
-810


Linear-equations/229002: Find the slope on the line containing pair of points: (7,5) and (10, -3)
m = ?
1 solutions

Answer 169872 by rfer(12730) About Me  on 2009-10-19 21:47:02 (Show Source):


Equations/228992: 6(x)-7=2(x)+29
54-7=18+29
47=47
I know the answer is x=9 But I do not understand how that is. If I were to take the test in this type of question,with different numbers, I wouldn't know how to do it at all! How would I figure these types of questions out? I am completely lost! Please help me!
With all appreciation,
Amber A
1 solutions

Answer 169870 by rfer(12730) About Me  on 2009-10-19 21:44:41 (Show Source):
You can put this solution on YOUR website!
follow the order of operation doing the multiplacation first
6(x)-7=2(x)+29
6x-7=2x+29
add 7
6x=2x+29+7
6x=2x+36
subtract 2x
4x=36
divide by 4
x=9
-------------------------------
54-7=18+29
combine like terms
47=47
correct


Miscellaneous_Word_Problems/228913: Write a situation that can be represented by the algebraic expression $3.25d.
1 solutions

Answer 169868 by rfer(12730) About Me  on 2009-10-19 21:37:44 (Show Source):
You can put this solution on YOUR website!
I receive an allowance of $3.25 a day.


Miscellaneous_Word_Problems/228911: Write an algebraic expression to represent the cost of a concert ticket h, with a service charge of $6.75
1 solutions

Answer 169865 by rfer(12730) About Me  on 2009-10-19 21:35:42 (Show Source):


Miscellaneous_Word_Problems/228912: Write an algebraic expression to represent the cost of m gallons of gasoline if each gallon costs $1.45.
1 solutions

Answer 169864 by rfer(12730) About Me  on 2009-10-19 21:33:46 (Show Source):


Linear-equations/228923: When trying to find x and y coordinates how do you use the "T" bar?
1 solutions

Answer 169861 by rfer(12730) About Me  on 2009-10-19 21:30:54 (Show Source):
You can put this solution on YOUR website!
your making an input output table
x on left y on right
after that plot them


Travel_Word_Problems/228987: What is the difference, in miles, between the two trains after each train travels for 6 hours?
Train L and train m leave a station at the same time heading in opposite directions. train l is going north at an average speed of 75 miles per hour. train m is giong south at an average speed of 60 mph?
1 solutions

Answer 169858 by rfer(12730) About Me  on 2009-10-19 21:28:30 (Show Source):
You can put this solution on YOUR website!
they are moving apart at 135 mph
D=rt
D=135*6
D=810 miles


Rational-functions/228919: how to graph f(x)=-1/2x-1
1 solutions

Answer 169856 by rfer(12730) About Me  on 2009-10-19 21:26:03 (Show Source):
You can put this solution on YOUR website!
you are given the slope of -1/2 and the y iny of -1 (same as (0,-1)
from the y int go 2 right 1 down for a second point and so on.


Divisibility_and_Prime_Numbers/228978: -5/8 divided by 3/4
1 solutions

Answer 169852 by rfer(12730) About Me  on 2009-10-19 21:20:42 (Show Source):
You can put this solution on YOUR website!
(-5/8)/(3/4)
invert and multiply
-5/8*4/3=-20/24=-5/6


Numbers_Word_Problems/228959: how can i find two consecutive odd integers whose sum is -88?
1 solutions

Answer 169849 by rfer(12730) About Me  on 2009-10-19 21:18:07 (Show Source):
You can put this solution on YOUR website!
x+2+x=-88
2x+2=-88
2x=-90
x=-45
x+2=-43