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Inequalities/387875: A line is described by the equation y=-2x+1. How would I graph this on a coordinate grid. And what is the value of x when y=999
How do i graph the inequality x-12> -7

1 solutions

Answer 274187 by rfer(12654) About Me  on 2010-12-19 15:52:27 (Show Source):
You can put this solution on YOUR website!
y=-2x+1
(1/2,0)
(0,1)
------------
999=-2x+1
998=-2x
x=998/-2
x=-499
------------------
x > 5
on the number line
circle around +5 with arrow to the right


Travel_Word_Problems/387876: A bicyclist leaves Bay Shore traveling at an average speed of 12 miles per hour.
Three hours later, a car leaves Bay Shore, on the same route, traveling at an
average speed of 30 miles per hour. How many hours after the car leaves Bay
Shore will the car catch up to the cyclist?
1 solutions

Answer 274186 by rfer(12654) About Me  on 2010-12-19 15:47:52 (Show Source):
You can put this solution on YOUR website!
36 miles lead
36/30=1 1/5 hrs=1hr 12min


Linear-equations/387840: Find the slope and y-intercept of the line. Write fractional answers in lowest terms. 2y + 7x + 6 = 11 + 7x.
The slope is: _?
The y-intercept is (0,_)?
1 solutions

Answer 274185 by rfer(12654) About Me  on 2010-12-19 15:45:44 (Show Source):
You can put this solution on YOUR website!
2y=-7x-6+11+7x
2y=5
y=5/2
(0,5/2)
any value of x equals y=5/2
no slope
horizontal line


Linear-equations/387842: Find the slope if it exists, of the line containing the pair of points.
(-14, -9) and (-15, -20).
The slope is: _?
1 solutions

Answer 274184 by rfer(12654) About Me  on 2010-12-19 15:41:08 (Show Source):
You can put this solution on YOUR website!
m=(-20--9)/(-15--14)
m=-11/-1
m=11


Rectangles/387873: how can i break down 480 square feet into equal length times width...whats the answer
1 solutions

Answer 274183 by rfer(12654) About Me  on 2010-12-19 15:37:55 (Show Source):


Numeric_Fractions/387843: Find the x and y intercepts and graph the equation plotting the intercepts. -7x-8y=56
1 solutions

Answer 274182 by rfer(12654) About Me  on 2010-12-19 15:36:23 (Show Source):
You can put this solution on YOUR website!
(-8,0)
(0,-7)


Numeric_Fractions/387858: 5x-49>6-8(2x+7)
1 solutions

Answer 274181 by rfer(12654) About Me  on 2010-12-19 15:34:41 (Show Source):
You can put this solution on YOUR website!
5x-49 > 6-16x-56
21x > -1
x > -1/21


Numbers_Word_Problems/387866: Does 1/5 x 1/6 = 1/30
1 solutions

Answer 274180 by rfer(12654) About Me  on 2010-12-19 15:30:46 (Show Source):


Polynomials-and-rational-expressions/387710: Multiply
-5x + 4
by
4x2 + x

1 solutions

Answer 274084 by rfer(12654) About Me  on 2010-12-18 23:12:38 (Show Source):
You can put this solution on YOUR website!
(-5x+4)(4x^2+x)
-20x^3-5x^2+16x^2+4x
-20x^3+11x^2+4x


test/387714: Is 120 the least common denominator of 12 and 21?
1 solutions

Answer 274081 by rfer(12654) About Me  on 2010-12-18 23:10:27 (Show Source):
You can put this solution on YOUR website!
least common denominator is 3
greatest common denominator is 84


Inequalities/387645: How do you find the solution to the inequality x-12 > -7
How can you factor the binomial 12x^2y^2 + 8xy^5 by finding the GCF.
1 solutions

Answer 274064 by rfer(12654) About Me  on 2010-12-18 20:50:06 (Show Source):
You can put this solution on YOUR website!
x-12 > -7
x > -7+12
x > 5
---------------
2xy^2(6x+4y^3)


Travel_Word_Problems/387669: Carlos and Robert leave Cabanatuan city at the same time. They are heading to BuLACAN. Carlos, driving his sports car, travels 65kph. Robert, on a motorcycle travels at 55 kph. How long will it be before they are 55km apart?
1 solutions

Answer 274062 by rfer(12654) About Me  on 2010-12-18 20:34:42 (Show Source):
You can put this solution on YOUR website!
moving apaprt at 10 kph
55/10=5.5 hrs


Polynomials-and-rational-expressions/387685: Chau runs 4 miles in 30 minutes. At the same rate, how many miles would he run in 24 minutes?
1 solutions

Answer 274061 by rfer(12654) About Me  on 2010-12-18 20:31:30 (Show Source):
You can put this solution on YOUR website!
4/30=x/24
30x=96
x=3.2 miles


Polynomials-and-rational-expressions/387687: Divide. Write your answer in lowest terms.
15xy/8x / 9y/5x
1 solutions

Answer 274060 by rfer(12654) About Me  on 2010-12-18 20:26:45 (Show Source):
You can put this solution on YOUR website!
invert and multiply
15xy/8x*5x/9y=75x^2y/40x^2=75y/40


Proportions/387684: Solve the following proportion for u:
10/u = -5/u - 3
1 solutions

Answer 274059 by rfer(12654) About Me  on 2010-12-18 20:23:22 (Show Source):
You can put this solution on YOUR website!
10u-30=-5u
-30=-15u
u=2


Polynomials-and-rational-expressions/387683: Solve the following proportion for u:
u/12 = 11/13
Round your answer to the nearest tenth.
1 solutions

Answer 274058 by rfer(12654) About Me  on 2010-12-18 20:20:30 (Show Source):
You can put this solution on YOUR website!
13u=132
u=10.2


Linear-equations/387679: find an equation of the line containing the givin pair of points (-5,-6) (-3,-1)
1 solutions

Answer 274055 by rfer(12654) About Me  on 2010-12-18 20:18:21 (Show Source):
You can put this solution on YOUR website!
m=-1--6/-3--5
m=5/2
-------------
y=mx+b
-1=5/2(-3)+b
-1=-15/2+b
-2/2+15/2=b
b=13/2
b=6.5
----------------
y=5/2x+6.5


Miscellaneous_Word_Problems/387674: The theoretical probability of undesirable side effects resulting from taking Grebex is 2 in 13. If 260 people take Grebex to lower their blood pressure, how many will encounter undesirable side effects?

1 solutions

Answer 274053 by rfer(12654) About Me  on 2010-12-18 20:05:02 (Show Source):
You can put this solution on YOUR website!
2/13=x/260
13x=520
x=40


Quadratic_Equations/387649: how do you simplify the exspression 6x3over3x4 with a 2 above the whole problem
1 solutions

Answer 274047 by rfer(12654) About Me  on 2010-12-18 19:27:48 (Show Source):
You can put this solution on YOUR website!
I think this is what you have
(6x^3/3x^4)^2
36x^6/9x^8
4x^-2
1/(4x^2)


Square-cubic-other-roots/387677: what is the answer to this question :
the square root of 50 times the square root of 2?
1 solutions

Answer 274044 by rfer(12654) About Me  on 2010-12-18 19:20:50 (Show Source):
You can put this solution on YOUR website!
sqrt(50*2)=
sqrt 100=10


Expressions-with-variables/387676: PLEASE HELP! THANK YOU.
Solve my substitution method.
6x+5y = 5 and
x = 30 - 5y. I know that in the second equation x is already solved for so I would substitute this into equation one right?
6(30 - 5y) + 5 = 5; 180 - 30y +5 = 5;
NOT SURE AFTER THIS.

1 solutions

Answer 274043 by rfer(12654) About Me  on 2010-12-18 19:19:10 (Show Source):
You can put this solution on YOUR website!
you have done the hard part except you lost the y with the first 5
180-30y+5y=5
-25y=-175
y=7
now plug in the 7
solve for x
6x+5*7=5
6x+35=5
6x=-30
x=-5
-------------------
-5=30-5*7


Surface-area/387665: What is the diameter of a circle that has an area of 106 square inches?
1 solutions

Answer 274041 by rfer(12654) About Me  on 2010-12-18 17:40:34 (Show Source):
You can put this solution on YOUR website!
A=pir^2
106/3.14=r^2
r^2=33.76
r=sqrt 33.76
r=5.81
D=2r
D=5.81*2
D=11.62 in


Equations/387644: how do you solve 26=8+v?
1 solutions

Answer 274040 by rfer(12654) About Me  on 2010-12-18 17:37:50 (Show Source):
You can put this solution on YOUR website!
26=8+v
subtract 8
26-8=v
18=v


Miscellaneous_Word_Problems/387663: Jocelyn has test scores of 75, 83 and 91 on her first three Algebra tests. What will she need to score on her 4th test so she will have an average of 85?
1 solutions

Answer 274039 by rfer(12654) About Me  on 2010-12-18 17:35:25 (Show Source):
You can put this solution on YOUR website!
(75+83+91+x)/4=85
249+x=85*4
x=340-249
x=91


Quadratic_Equations/387648: how do you simplify the exspression a3b2 over a2b

1 solutions

Answer 274038 by rfer(12654) About Me  on 2010-12-18 17:32:55 (Show Source):
You can put this solution on YOUR website!
a^3b^2/a^2b
a^3-a^2=a
b^2-b^1=b
=ab


Quadratic_Equations/387654: how do you simplify the exspression r-3s5t2over r2st-2
1 solutions

Answer 274037 by rfer(12654) About Me  on 2010-12-18 17:25:43 (Show Source):


Graphs/387624: Write the slope-intercept equation for the line that passes through (2, -7) and (4, -13). Please show all of your work.
1 solutions

Answer 274021 by rfer(12654) About Me  on 2010-12-18 15:38:09 (Show Source):
You can put this solution on YOUR website!
m= (-13--7)/(4-2)
m=-6/2
m=-3
---------------
y=mx+b
-7=-3*2+b
b=-1
----------------
y=-3x-1


Linear-equations/387629: Consider the lines y = 3x + 7 and x + 2y = -10
Are the lines parallel? Explain why by comparing the slopes of the lines.



Are the lines perpendicular? Explain why by comparing the slopes of the lines.




Do the lines intersect? Explain why.

1 solutions

Answer 274019 by rfer(12654) About Me  on 2010-12-18 15:33:59 (Show Source):
You can put this solution on YOUR website!
y=3x+7
2y=-x-10
y=-1/2x-5
1st part
no
2nd part
no
3rd part
yes at (-3,-3.5)
I will let you do the explanations


Polynomials-and-rational-expressions/387631: can someone help me with this problem? It is a fraction.
3x^2 - 5x over 18x - 30
1 solutions

Answer 274018 by rfer(12654) About Me  on 2010-12-18 15:26:18 (Show Source):
You can put this solution on YOUR website!
3x^2-5x/18x-30
1/6x with remainder of 0


Inequalities/387600: Why do you flip the inequality sign when dividing by a negative number?
1 solutions

Answer 274006 by rfer(12654) About Me  on 2010-12-18 13:43:34 (Show Source):
You can put this solution on YOUR website!
referr to
themathpage.com
and look at inequalities.
The have some nice examples


Human-and-algebraic-language/387599: I need help with all math ( ASAP )
1 solutions

Answer 274005 by rfer(12654) About Me  on 2010-12-18 13:29:07 (Show Source):
You can put this solution on YOUR website!
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