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Expressions-with-variables/229717: v - 15 = -27
1 solutions

Answer 170243 by rfer(12657) About Me  on 2009-10-21 14:24:20 (Show Source):
You can put this solution on YOUR website!
v-15=-27
v=-12


Problems-with-consecutive-odd-even-integers/229723: multiply.

(-12)(-4)=
(-3)(10)=
2000(5432)(-8)(0)=
1 solutions

Answer 170241 by rfer(12657) About Me  on 2009-10-21 14:23:09 (Show Source):
You can put this solution on YOUR website!
+48
-30
-8.6912x10^7


Problems-with-consecutive-odd-even-integers/229720: add
-16+(-7)=
-23+3.7=
-5 1/2+(-2 1/2)=
1 solutions

Answer 170240 by rfer(12657) About Me  on 2009-10-21 14:20:49 (Show Source):


Graphs/229650: Find the intercepts for the equation.
x + y = 1
1 solutions

Answer 170222 by rfer(12657) About Me  on 2009-10-21 13:36:42 (Show Source):
You can put this solution on YOUR website!
x+y=1
0+y=1
x+0=1
y int=(0,1)
x int=(1,0)


Graphs/229652: Find the slope and the y-intercept of the line.
-3x + y = 14
1 solutions

Answer 170220 by rfer(12657) About Me  on 2009-10-21 13:31:07 (Show Source):
You can put this solution on YOUR website!
y=mx+b
y=3x+14
slope=m=3
y int=b=14 (0,14)


Expressions-with-variables/229660: Find the x- and y-intercepts for 3x + 2y = 8.
Please help, thank you.
1 solutions

Answer 170217 by rfer(12657) About Me  on 2009-10-21 13:26:59 (Show Source):
You can put this solution on YOUR website!
y int= (0,4)
x int= (8/3,0) or (2 2/3,0)


Equations/229673: Two trains leave Chicago, one traveling east @ 30 mph and one traveling west @ 40 mph. When will the trains be 210 miles apart? Answer 3 hrs., but how do you set up the problem?
1 solutions

Answer 170215 by rfer(12657) About Me  on 2009-10-21 13:24:54 (Show Source):
You can put this solution on YOUR website!
moving away from each other at 70 mph
210/70=3 hrs


Equations/229671: Two cyclists begin traveling in the same direction on the same bike path. One travels at 15 mph, and the other travels at 12 mph. When will the cyclists be 10 miles apart?
1 solutions

Answer 170214 by rfer(12657) About Me  on 2009-10-21 13:22:38 (Show Source):
You can put this solution on YOUR website!
speed moving apart equals 3 mph
10/3=3 1/3 hrs=3 hrs 20 min


Polynomials-and-rational-expressions/229659: (x+5)(x+2)find the product
1 solutions

Answer 170213 by rfer(12657) About Me  on 2009-10-21 13:20:34 (Show Source):
You can put this solution on YOUR website!
(x+5)(x+2)
x^2+2x+5x+10
x^2+7x+10


Expressions-with-variables/229665: x%2F4 - 6 = 1
Please help me find x, thank you.
1 solutions

Answer 170212 by rfer(12657) About Me  on 2009-10-21 13:18:57 (Show Source):
You can put this solution on YOUR website!
x/4-6=1
x/4=7
x=7*4
x=28


Expressions-with-variables/229667: 9x - 2 = 13

1 solutions

Answer 170211 by rfer(12657) About Me  on 2009-10-21 13:17:34 (Show Source):
You can put this solution on YOUR website!
9x-2=13
9x=15
x=15/9
x=1 2/3


Equations/229577: solve and check your answer
a/4=7/2_
1 solutions

Answer 170207 by rfer(12657) About Me  on 2009-10-21 12:23:27 (Show Source):
You can put this solution on YOUR website!
a/4=7/2
a=(7/2)(4/1)
a=28/2
a=14


Distributive-associative-commutative-properties/229590: (-y-9)(-5)
1 solutions

Answer 170205 by rfer(12657) About Me  on 2009-10-21 12:07:37 (Show Source):
You can put this solution on YOUR website!
(-y-9)(-5)
5y+45


Problems-with-consecutive-odd-even-integers/229596: find four consecutive integers whose sum is 62
1 solutions

Answer 170204 by rfer(12657) About Me  on 2009-10-21 12:06:37 (Show Source):
You can put this solution on YOUR website!
x+x+1+x+2+x+3=62
4x=56
x=14
x+1=15
x+2=16
x+3=17


Polynomials-and-rational-expressions/229606: Multiply
(4x+4)(5x^2+4x+9)
1 solutions

Answer 170203 by rfer(12657) About Me  on 2009-10-21 12:03:34 (Show Source):
You can put this solution on YOUR website!
20x^3+16x^2+36x+20x^2+16x+36
20x^3+36x^2+52x+36


Polynomials-and-rational-expressions/229604: Multiply.
(w+1/5)(w+1/4)
1 solutions

Answer 170202 by rfer(12657) About Me  on 2009-10-21 12:00:28 (Show Source):
You can put this solution on YOUR website!
w^2+1/4w+1/5w+1/5*1/4
w^2+9/20w+1/20


Age_Word_Problems/229369: ruby an emily are twins. rebecca is 6 more than 2 times Ruby and Emily's age. Altogether the sum of their threee ages is 50.how old are emily and Ruby?
1 solutions

Answer 170141 by rfer(12657) About Me  on 2009-10-21 00:07:34 (Show Source):
You can put this solution on YOUR website!
2x+2x+6=50
4x=44
x=11 yrs


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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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(12657) 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