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Equations/254374: -3.4-(-7.6)=
1 solutions

Answer 186719 by richwmiller(9135) About Me  on 2010-01-06 22:13:42 (Show Source):
You can put this solution on YOUR website!
We are adding numbers or subtracting numbers
-3.4-(-7.6)=
-3.4+7.6=
rearrange so it looks better (not necessary but most people feel better about it)
7.6-3.4=
Now you should be able to do this.


Radicals/254381: could u guys pleae help me negative 3 squared 120 whats the radical expression
1 solutions

Answer 186718 by richwmiller(9135) About Me  on 2010-01-06 22:10:55 (Show Source):
You can put this solution on YOUR website!
(-3)^2
I don't know what you want done with 120


Word_Problems_With_Coins/254385: You have $5.60 in half-dollars. The number of dimes is 7 less than twice the number of half-dollars.
How many dimes do you have?
How many half-dollars do you have?
1 solutions

Answer 186717 by richwmiller(9135) About Me  on 2010-01-06 22:09:17 (Show Source):
You can put this solution on YOUR website!
You can't have $5.60 in half dollars


Radicals/254379: am doing simplify radiacl expression could u show me how to work - squared 80
1 solutions

Answer 186715 by richwmiller(9135) About Me  on 2010-01-06 22:06:47 (Show Source):
You can put this solution on YOUR website!
Do you mean sqrt(80)?
Do you want the squareroot or the square?
sqrt(80)=sqrt(4*20)=4sqrt(5)
Find factors of the numbers involved.
(4*4)*5=80
5 is prime and has no factors


Square-cubic-other-roots/254384: I am trying to arrive at a decimal approximation for the radius of a sphere that has a volume of 641,431,000 cubic kilometers.
1 solutions

Answer 186714 by richwmiller(9135) About Me  on 2010-01-06 22:01:17 (Show Source):
You can put this solution on YOUR website!
v=4/3pi*r^3
641,431,000=4/3pi*r^3
r=535


Parallelograms/254376: Please help me solve this problem.
Find the values of x and y that ensure each quadrilateral is a parallelogram.

Top of quadrilaterial is: 3x-4y
Bottom of quadrilaterial is: 18
Right of it is: 7
Left of it is: 5x+y
1 solutions

Answer 186708 by richwmiller(9135) About Me  on 2010-01-06 21:18:46 (Show Source):
You can put this solution on YOUR website!
set the top and bottoms equal and the right and left equal and solve them as a system of linear equations
3x-4y=18
5x+y=7
x=2 y=-3


Square-cubic-other-roots/254375: i like to solve this problem
A(0,5) B(5V`3,2),C(0-1)
1 solutions

Answer 186707 by richwmiller(9135) About Me  on 2010-01-06 21:11:36 (Show Source):
You can put this solution on YOUR website!
What is the question?


Linear-systems/254356: Factor the expression 8x^4 - 8x^3 - 6x^2
1 solutions

Answer 186704 by richwmiller(9135) About Me  on 2010-01-06 21:01:48 (Show Source):
You can put this solution on YOUR website!
more factoring
2 x^2 (2 x-3) (2 x+1)


Linear-equations/254318: What is the value of k if the line 2x + 3y = 3 is perpendicular to the line 2x + ky + 1 = 0?
1 solutions

Answer 186674 by richwmiller(9135) About Me  on 2010-01-06 18:57:14 (Show Source):


Percentage-and-ratio-word-problems/254313: here are the figures. cross oak height is 11 and the spread is 3. the white oak height is 96 and the spread is 119. I need to know the following: the height of the cross oak is what fraction of the height of the white oak. Then 2nd the spread of the cross oak is what percent of the spread of the white oak. Thank you
1 solutions

Answer 186666 by richwmiller(9135) About Me  on 2010-01-06 18:44:04 (Show Source):
You can put this solution on YOUR website!
co h 11 s 3
wo h 96 s 119
11/96=coh/woh
ok
3/119=cos/wos
3*100/119=divide this out for percent


Exponents/254315: How many digits does 2^15 * 5^8 have when expanded?
1 solutions

Answer 186662 by richwmiller(9135) About Me  on 2010-01-06 18:38:45 (Show Source):
You can put this solution on YOUR website!
11 digits
12 800 000 000


Numbers_Word_Problems/254316: find the consecutive positive integers whose twice the product is 684
1 solutions

Answer 186657 by richwmiller(9135) About Me  on 2010-01-06 18:35:05 (Show Source):
You can put this solution on YOUR website!
n*(n+1)*2=684


Miscellaneous_Word_Problems/254293: Tickets for a basketball game cost $6.00 for adults and $3.00 for students. A total of 846 tickets that cost $3846.00 were sold. How many of each were sold?
1 solutions

Answer 186656 by richwmiller(9135) About Me  on 2010-01-06 18:34:07 (Show Source):
You can put this solution on YOUR website!
I will set this up
a+s=846
a=846-s
6a+3s=3846
substitute 846-s for a above
6(846-s)+3s=3846


Numbers_Word_Problems/254299: find the lesser of two consecutive numbers with a sum greater than 16
1 solutions

Answer 186648 by richwmiller(9135) About Me  on 2010-01-06 18:27:12 (Show Source):
You can put this solution on YOUR website!
I just did this for sum 20
n+n+1=16
2n=15
n=7.5
7.5 is not an integer
I am sure your problem meant to say integer or it wouldn't say consecutive.
7 and 8 aren't big enough.
So we try 8 and 9
Sure enough they equal 17
So the answer is 8 the lesser of the two (8 and 9)



Average/254296: Find the area of a circle. Use 3.14 or 22/7
Diameter = 7ft
Answer = ?
PLEASE HELP!!!!!!
1 solutions

Answer 186644 by richwmiller(9135) About Me  on 2010-01-06 18:19:51 (Show Source):
You can put this solution on YOUR website!
I will set it up for you.
d=2r
7=2r
7/2=r
3.5=r
A=pi*r^2
A=22/7*(7/2)^2
A=(22/7)*(7*7/(2*2)
A=(22*7*7)/(7*2*2)
I think you can see some cancelling to do
At least 2/2 and 7/7 which is why I chose 22/7 rather than 3.14 for pi and left the radius as 7/2


Quadratic_Equations/254294: I need to solve this equation with the quadratic formula.
m%5E2%2B12m%2B5=0
What i got was -6 + or - Squareroot of 31
I have done this twice but i seem to get it wrong every time then i also got -12 + or - squareroot of 31 and that was wrong to please help me.
1 solutions

Answer 186639 by richwmiller(9135) About Me  on 2010-01-06 18:11:46 (Show Source):
You can put this solution on YOUR website!

The right answer is no prettier than your answer.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation am%5E2%2Bbm%2Bc=0 (in our case 1m%5E2%2B12m%2B5+=+0) has the following solutons:

m%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%2812%29%5E2-4%2A1%2A5=124.

Discriminant d=124 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-12%2B-sqrt%28+124+%29%29%2F2%5Ca.

m%5B1%5D+=+%28-%2812%29%2Bsqrt%28+124+%29%29%2F2%5C1+=+-0.432235637169978
m%5B2%5D+=+%28-%2812%29-sqrt%28+124+%29%29%2F2%5C1+=+-11.56776436283

Quadratic expression 1m%5E2%2B12m%2B5 can be factored:
1m%5E2%2B12m%2B5+=+1%28m--0.432235637169978%29%2A%28m--11.56776436283%29
Again, the answer is: -0.432235637169978, -11.56776436283. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B12%2Ax%2B5+%29


Linear-equations/254282: I am trying to help my daughter.
she was learning ax(squared) + bx + c = y, which she understands.
However she was given
vertex (2, -3)
contains points (-1,-12)
y-k=a(x-h)squared
she has to find "a"
then plug in to the vertix form to find the ax form
1 solutions

Answer 186636 by richwmiller(9135) About Me  on 2010-01-06 18:07:18 (Show Source):
You can put this solution on YOUR website!
(h,k) are the vertex coordinates
So plug those in
(2, -3) for (h,k)
(-1,-12) for (x,y)
y-k=a(x-h)^2
-12-(-3)=a(-1-2)^2
Mind your signs
-12+3=a(-3)^2
remember (-3)^2=+9
-9=a+(9)
-1=a


Problems-with-consecutive-odd-even-integers/254285: find the two least consecutive integers whose sum is greater then 20.
n+(n+1)>20 i did this and came out with 9.5 whose sum is not greater then 20. i need help!
1 solutions

Answer 186631 by richwmiller(9135) About Me  on 2010-01-06 17:52:24 (Show Source):
You can put this solution on YOUR website!
9.5 is not an integer.
9 and 10 are not large enough
So 10 and 11 are the integers
whole numbers like -23, 0 and 334
n+n+1=20


Polygons/254287: what is the area of the polygon if the top is 12 inches and the side is 7 inches
1 solutions

Answer 186630 by richwmiller(9135) About Me  on 2010-01-06 17:48:36 (Show Source):
You can put this solution on YOUR website!
It would be nice to know how many sides are of those sizes.


Miscellaneous_Word_Problems/254286: The tickets to a winter concert cost $20.70 for the lower level and $6.75 for the upper level. A total of 14,000 tickets were sold for a total amount of $220,050. How many lower level tickets were sold?

* please add the work. thank you...
1 solutions

Answer 186629 by richwmiller(9135) About Me  on 2010-01-06 17:47:30 (Show Source):
You can put this solution on YOUR website!
I suspect you mean, "Please, include the work."
The work is not extra.
But I am not going to solve it for you.
I will set up the equation and you get to have all the fun
l=lower level tickets sold
u=upper level tickets sold
20.70l+6.75u=220050
u+l=14000
Have fun at the concert. Who's playing?
ok you talked me into it.
9000 =l


Polynomials-and-rational-expressions/254283: Writing this function in factored form:
y=4x^3-49x
1 solutions

Answer 186624 by richwmiller(9135) About Me  on 2010-01-06 17:41:02 (Show Source):
You can put this solution on YOUR website!
The first thing we can see even without glasses is that we can factor out x
y=x*(4x^2-49)
oh that looks like a product of + and - where the x term gets cancelled out
y = x*(2 x-7)*(2 x+7)


Mixture_Word_Problems/254281: Lemon drops and jelly beans are mixed to make a 100 pound mix. If the lemon drops cost $1.90 per pound and jelly beans cost $1.20 per pound, how many pounds of lemon drops are needed to make the mix cost $1.48 per pound?
1 solutions

Answer 186623 by richwmiller(9135) About Me  on 2010-01-06 17:36:10 (Show Source):
You can put this solution on YOUR website!
l=lemon drops
j=jelly beans
l+j=100
l*1.90+j*1.20=100*148
j=60 and l=40


Travel_Word_Problems/254279: A winter storm is traveling at a constant rate of 50 miles per hour. The storm is over St. Louis at 6:00 pm. At what time will the storm hit Indianapolis if the two cities are 242 miles apart?
1 solutions

Answer 186621 by richwmiller(9135) About Me  on 2010-01-06 17:31:22 (Show Source):
You can put this solution on YOUR website!
I like this much better than the imaginary cars and trains.
rt=d
50*x=242
Solve for x and add x to 6:00pm
multiply the decimal part of the answer by 60 to get minutes
For example if the answer were 3.25 then you would multiply .25*60 to get 15 minutes
then if that has a decimal do the same to get seconds
So your answer might be something like 3 hours 45 minutes and 40 seconds.
You then would add that to 6:00 to get 9:45:40 pm

But that is not your answer.
Good luck


Mixture_Word_Problems/249696: Two liters of 40% acid are mixed with 4 liters of another acid to form a 50% acid solution. What is the strength of the added acid?
1 solutions

Answer 186616 by richwmiller(9135) About Me  on 2010-01-06 17:21:49 (Show Source):
You can put this solution on YOUR website!
.4*2+4*a=.50*(6)
Solve for a and convert to percent


Graphs/254264: I need to graph y=2x-1, y=x+2
1 solutions

Answer 186612 by richwmiller(9135) About Me  on 2010-01-06 17:16:06 (Show Source):
You can put this solution on YOUR website!
I like your math teacher already. Your teacher is promoting good clean fun better than Mario video games, haha lol.
Solve each for x=0 and y=0
That will give you two points for each equation. They are both lines so you only need two points each.
They meet and cross at (3,5)
I'll even give another hint which will solve x=0
The numbers at the end of each equation are when x=0 -1 and +2


Polygons/254271: Find the number of sides an equilangular polygon has if each of its angles(interior) is
a. 144 (degrees)
b. 120 (degrees)
c. 156 (degrees)
d. 162 (degrees)
e. 172 4/5 (degrees)
1 solutions

Answer 186606 by richwmiller(9135) About Me  on 2010-01-06 17:09:41 (Show Source):
You can put this solution on YOUR website!
The rules say submit only one example of your problem type.
No similar problems.


Pythagorean-theorem/254278: if the hypotenuse of a right triangle is 15cm long and one leg is 9 how long is the other leg?
1 solutions

Answer 186604 by richwmiller(9135) About Me  on 2010-01-06 17:07:15 (Show Source):
You can put this solution on YOUR website!
a^2+b^2=c^2 where and b are the legs of the right triangle and c is the hypotenuse
substitute 15 for c and 9 for a and solve for b
9^2+b^2=15^2


Graphs/254276: How do you find the slope of different angles on a geometric shape?
1 solutions

Answer 186603 by richwmiller(9135) About Me  on 2010-01-06 17:04:52 (Show Source):
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resubmit with an example


Graphs/254272: describe in words the curve of the below
(x+2)^2+(y-4)^2=36
how is this done without graphing?
1 solutions

Answer 186602 by richwmiller(9135) About Me  on 2010-01-06 17:03:55 (Show Source):
You can put this solution on YOUR website!
Various equations are known to produce different figures.
y=mx+b produces a straight line.
Your equation produces a circle.
(x-h)2 + (y-k)2=r2
where r is the radius
h and k are the center of the circle x and y


Parallelograms/254273: Two of the angles of a parallelogram each measure 75 degrees. What are the measures of the other two angles? Explain your reasoning.
1 solutions

Answer 186599 by richwmiller(9135) About Me  on 2010-01-06 16:57:08 (Show Source):
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The last I knew parallelograms were not triangles so I moved your problem.
Is that a problem :)
Hints :
the angles of all parallelograms(including rectangles and squares) add up to 360
The angles in a parallelogram come in two equal pairs
You already know one pair (two of them) is each 75 degrees
So if the total is 360 and we have 150(2*75) what would th3e other two add up to?
And if we know what they add up to, we just have to divide that by 2 to get each angles of the pair


Graphs/254274: find the slope of each line
3y2x and 4x 0y
1 solutions

Answer 186598 by richwmiller(9135) About Me  on 2010-01-06 16:50:47 (Show Source):
You can put this solution on YOUR website!
Sorry but those are not equations.
And therefore are not lines
What they should be is any bodies guess