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unlockmath answered: 1598 problems
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Circles/307394:
Point C is the center of the circle. What is the measure of angle ACB if the measure of arc ADB is equal to 201 degrees
1 solutions
Answer 219900 by unlockmath(1599)   on 2010-05-22 17:07:03 (Show Source):
You can put this solution on YOUR website!Hello,
Since a circle has 360 degrees all we need to do is subtract 201 from 360 to get:
159 degrees
(Note: There really isn't enough info but I'm guessing point D is in the smaller arc)
RJ
Make Sense?
www.math-unlock.com
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Linear-equations/306641: Find the intercept of the graph of this equation. 8x-3y=24
1 solutions
Answer 219418 by unlockmath(1599) on 2010-05-19 23:35:09 (Show Source):
You can put this solution on YOUR website!Hello,
If you want the y intercept then let's get the equation in the form of
y=mx+b (Hint: b is the y intercept)
8x-3y=24 Subtract 8x and divide by -3 to get:
y=-8/3(x)-3
OK, now we know that -3 on the y axis is where the line passes through.
Make sense?
RJ
www.math-unlock.com
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Expressions-with-variables/304790: (3x^2+2x-3)-(x^2-2x+1)
I have an answer of -4+4x=2x^2 Is this correct?
1 solutions
Answer 218267 by unlockmath(1599) on 2010-05-15 12:35:05 (Show Source):
You can put this solution on YOUR website!Hello,
First off we can write this (3x^2+2x-3)-(x^2-2x+1) as:
3x^2+2x-3-x^2+2x-1 Now combine like terms to get:
2x^2+4x-4 We can rewrite this as:
2(x^2+2x-2)
There we go. This is simplified.
I don't see the original as an equation. It's an expression. Equations have equal signs and expression stand alone.
RJ
Make sense?
www.math-unlock.com
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Rectangles/304042: How many three foot wide pieces of fencing are needed to surround the perimeter of
a yard that is 15 feet long and 24 feet wide?
1 solutions
Answer 217829 by unlockmath(1599) on 2010-05-13 00:26:53 (Show Source):
You can put this solution on YOUR website!Hello,
First let's find the perimeter.
It works out to 78 feet.
Now divide this by 3 to get:
26 pieces of fencing
Make sense?
RJ
www.math-unlock.com
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Miscellaneous_Word_Problems/304060: The sum of two numbers is 22. Three times the smaller number minus two times the larger number is negitive 29. What is the smaller number?
1 solutions
Answer 217822 by unlockmath(1599) on 2010-05-12 23:50:53 (Show Source):
You can put this solution on YOUR website!Hello,
Let's have x & y represent the numbers. We can set up 2 equations as:
x+y=22
3x-2y=-29 Let's use substitution by changing the first equation to:
x=22-y
And plug this into the second.
3(22-y)-2y=-29 Rewritten as:
66-3y-2y=-29 Combine like terms and subtract 66 from both sides to get:
-5y=-95 Divide both sides by -5 to get:
y=19
Solve x by plugging this into either equation.
x+19=22
x=3
Check it out to see if these work.
RJ
www.math-unlock.com
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Age_Word_Problems/302367: One number is 4 more than another, and their sum is 60. What is the smaller number?
1 solutions
Answer 216806 by unlockmath(1599) on 2010-05-09 17:17:24 (Show Source):
You can put this solution on YOUR website!Hello,
Let x be the number so the equation will be:
x+(x+4)=60 Rewritten as:
2x+4=60 Subtract 4 and divide by 2 from both sides to get:
x=28
There we go. Make sense?
RJ
Check out a book I wrote:
www.math-unlock.com
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Graphs/301746: 6x+y=44
6x+7y=28
I do it this way correct:
6x+7y(44-6x)=28
6x=308-42x=28
48x+308=28
co efficient is 48
48x+308=28
48x-336
x=7
y=44 -6(7x)
44-42
y = 2
1 solutions
Answer 216372 by unlockmath(1599) on 2010-05-07 16:33:32 (Show Source):
You can put this solution on YOUR website!Hello,
Let's go through each step.
6x+y=44
6x+7y=28
First equation rewritten as:
y=44-6x Plug this into the second equation to get:
6x+7(44-6x)=28
6x+308-42x=28
-36x+308=28
From this point we subtract 308 from both sides to get:
-36x=-280 Divide -36 into both sides to get:
x=280/36 reduced to 70/9
x=70/9
Plug this into either equation:
6(70/9)+7y=28 Do the math:
7y=28-(140/3)
y=-8/3
Check the answer by plugging these answers into either original equation.
Make sense?
RJ
Get a book I wrote on the basics of math at:
www.math-unlock.com
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Quadratic_Equations/300971: the length of a rectangle is 9cm longer then the width. The area of the rectangle is 90cm. What are the dimensions of the rectangle ?
1 solutions
Answer 215850 by unlockmath(1599) on 2010-05-05 17:32:14 (Show Source):
You can put this solution on YOUR website!Hello,
Let x be the width and x+9 be the length. The equation will be:
x(x+9)=90 Rewritten as:
x^2+9x-90=0 Factor this to:
(x-6)(x+15)=0 Solve for x:
x=6
x=-15
The obvious answer is 6 cm for the width and 15 cm for the length.
Make sense?
RJ
Check out a book I wrote at:
www.math-unlock.com
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Rectangles/300839: What would be the dimensions if the area of a table is 1650in and the length is 17 inches more than the width?
1 solutions
Answer 215796 by unlockmath(1599) on 2010-05-05 13:07:56 (Show Source):
You can put this solution on YOUR website!Hello,
We can use x to show the width and x+17 to be the length. Now we can set up the following equation: (Note: it should be 1650 Square inches)
x(x+17)=1650 Rewritten to look:
x^2+17x-1650=0 Factor this to get:
(x-33)(x+50)=0 Solve x:
x=33
x=-50
The obvious answer is 33 so the width is 33 inches and length is 50 inches.
Make sense?
Check out a book I wrote on the basics of math:
www.math-unlock.com
|
Finance/300844: Tom took a trip of 1,300 miles. He traveled by train at 50 miles an hour and the same number of hours by plane at 275 mph
1 solutions
Answer 215793 by unlockmath(1599) on 2010-05-05 12:59:28 (Show Source):
You can put this solution on YOUR website!Hello,
Let's have x represent the hours tom traveled. The equation will look like:
50x+275x=1300 Combine like terms to get:
325x=1300 Divide both sides by 325 to get:
x=4 So it took 4 hours by each method of travel.
Make Sense?
RJ
www.math-unlock.com
|
Finance/300114: one third of a number, decreased by thirty six, is at most twenty two. Find the number
1 solutions
Answer 215423 by unlockmath(1599) on 2010-05-03 20:14:04 (Show Source):
You can put this solution on YOUR website!Hello, Let's have x be the number. Here's the equation we can wet up;
1/3(x)-36<=22 Add 36 and multiply 3 to both sides to get:
x<=174
Make sense?
Plug in the answer to see if it works.
RJ
Check out a book I wrote:
www.math-unlock.com
|
Triangles/300123: A right angled triangle has a perimeter of 120 cm. If the hypotenuse is 50 cm, what is the length of the other two sides?
1 solutions
Answer 215421 by unlockmath(1599) on 2010-05-03 20:07:58 (Show Source):
You can put this solution on YOUR website!Hello,
More data is needed. If the triangle is an isosceles triangle then we could solve it with the Pythagorean Theorem.
RJ
www.math-unlock.com
|
Expressions-with-variables/299862: 2) Suppose that the width of a rectangle is 5 inches shorter than the length and that the perimeter of the rectangle is 50 inches. The formula for the perimeter of a rectangle is P=2L+2W.
a) Set up an equation for the perimeter involving only L, the length of the rectangle.
Answer:
b) Solve this equation algebraically to find the length of the rectangle. Find the width as well.
Answer: Length ______, Width ______
Show your work here:
1 solutions
Answer 215310 by unlockmath(1599) on 2010-05-03 12:22:02 (Show Source):
You can put this solution on YOUR website!Hello,
Let's show width as L-5 then we can set up this equation as:
2(L-5)+2L=50 Combine like terms to get:
4L-10=50 Add 10 and divide 4 to get:
L=15 inches
So now we know the width is 10 inches.
Make sense?
Check out a book I wrote at:
www.math-unlock.com
|
Geometry_Word_Problems/299378: A 20-foot monument casts a shadow 32- feet long. How long of a shadow would a 6- foot man cast at the same time?
1 solutions
Answer 215131 by unlockmath(1599) on 2010-05-02 14:47:12 (Show Source):
You can put this solution on YOUR website!Hello,
This we can set up as a proportion as follows:
20/32=6/x (x will represent the shadow of the man)Following me?
Cross multiply to get:
20x=192 Divide by 20 to get:
x=9.6 feet
Make sense?
RJ
There's a book I wrote on the basics:
www.math-unlock.com
|
Miscellaneous_Word_Problems/299387: Clair and Anna were both saving for airline tickets to Washington DC. On Dec 1st Clair was $95 short of the amount she needed and Anna was $83 short of the amount she needed. If they combined their money, they had exactly enough for one ticket. How much did the airline ticket cost?
WE're confused because they didn't tell us how much money they had to begin with.
1 solutions
Answer 215130 by unlockmath(1599) on 2010-05-02 14:35:00 (Show Source):
You can put this solution on YOUR website!Hello,
Let's have x represent the price of one ticket so we can show this as:
Clair (x-95)
Anna (x-83)
Now if we combine the two it equals 1 ticket, Right?
So an equation can be set up like this:
(x-95)+(x-83)=x Combine like terms we get:
2x-178=x Now subtract x and add 178 to both sides and we get:
x=178
There we go the price of one ticket is:
$178.00
Make sense?
RJ
Check out a book I wrote on the basics:
www.math-unlock.com
|
Systems-of-equations/299381: solve the equation 2x-3y=12 and x+y=4
1 solutions
Answer 215127 by unlockmath(1599) on 2010-05-02 14:07:15 (Show Source):
You can put this solution on YOUR website!Hello,
Let's use substitution for these:
2x-3y=12
x+y=4 Subtract y from both sides to get:
x=4-y Now we can plug this into the first equation to get:
2(4-y)-3y=12 Are you with me? OK now solve for y:
8-2y-3y=12 Subtract 8 and divide by -5 to get:
y=-4/5
From here plug this into either of the original equations. I'll choose the second one.
x+(-4/5)=4 Add 4/5 to both sides and:
x=4 4/5
You can check these answers by plugging it into either equation.
Make Sense?
RJ
www.math-unlock.com
|
Numeric_Fractions/299107: how would do this fraction and reduce to lower 3 3/45 + 9 6/45
1 solutions
Answer 215030 by unlockmath(1599) on 2010-05-01 16:01:08 (Show Source):
You can put this solution on YOUR website!Hello,
Since you have two fractions with common denominators all we need to do is add:
3 3/45 + 9 6/45 We'll get:
12 9/45 This can be reduced down to:
12 1/5
Make sense?
RJ
There's a book I wrote on the basics of math that might help:
www.math-unlock.com
|
Volume/299090: Find the surface area, to the nearest tenth, of a cylinder with diameter 5cm and height 8cm. (S=2 pi rh+2 pi r2).
1 solutions
Answer 215029 by unlockmath(1599) on 2010-05-01 15:53:55 (Show Source):
You can put this solution on YOUR website!Hello,
Since we know the formula is S=2 pi rh+2 pi r2 all we need to do is plug in the values we know to get:
S=2 pi 2.5(8)+ 2 pi 2.5^2 Do the calculation and we get:
S=40 pi + 12.5 pi Combine to get:
S=52.5 pi square cm We could plug in 3.14 for pi to get:
164.9 sq cm (rounded to the nearest tenth)
Make Sense?
RJ Check out a book I wrote on the basics of math:
www.math-unlock.com
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