All Answers 358525 Answers

Because 1+1=2, not window, not 11, 2. 1+1=2, 2+2=4, 9+10=19. ALL OF THE QUESTIONS THAT ASK THOSE SAME PROBLEMS ARE THE CANCER OF THIS SITE. 

Ok, here's the thing. The thing here is that someone who was here everyday just up and left, firstly. Secondly, the grammar on this site sometimes is ATROCIOUS. Thirdly, this is a forum to help people with math and most math teachers only accept the problem with WORK INCLUDED. Finally, judgment is a big topic, and I feel it deserves an off-topic where we can discuss it CALMLY. That means no pointing fingers, keeping it anonymous, etc. If the name is shown in the picture, edit it out. P.S. We need to work together on this stuff, not argue about it. We are like a family, family fights, but we are supposed to team up to help out, within the family an outside the family, k? 

P.P.S Wow that was a long rant... 

Area  of top and bottom  = 2[ pi*R^2  - pi*r^2]  =  2pi[ R^2  - r^2]  = 2pi(R + r) (R - r)

Area  of inside of smaller cylinder  = 2*pi*r*h

Area of outside of larger cylinder = 2*pi*R*h

Total Lateral (side) surface area  = 2*pi*h*[R + r]

Total surface area = 2*pi(R + r) (R - r) + 2*pi*h*[R + r]  = 2*pi*[R + r] [ h + R - r] =

2*pi * [ (6 + 3)mm] [(18 + 6 - 3) mm]  = 1187.52 mm^2

Calc, I feel like smacking you across the face rn...

So, uh, you kinda got some grammar there... That needs fixing. :| 

Find the surface area of the figure. Round your answer to the nearest hundredth.

H; 18mm

R; 6mm

r; 3mm

\(\begin{array}{lrcll} \text{Area inside is a cylinder with radius r } & A_i &=& ( 2\pi r ) \cdot h \\ \text{Area outside is a cylinder with radius R } & A_o &=& ( 2\pi R ) \cdot h \\ \text{Area top is a ring } & A_{r_1} &=& \pi R^2 - \pi r^2 \\ \text{Area bottom is a ring } & A_{r_2} &=& \pi R^2 - \pi r^2 \\ \hline \\ \text{Area of the figure is the sum } \\ \end{array}\\ \begin{array}{lrcll} & A &=& A_i + A_o + A_{r_1} + A_{r_2} \\ & A &=& ( 2\pi r ) \cdot h + ( 2\pi R ) \cdot h + \pi R^2 - \pi r^2 + \pi R^2 - \pi r^2 \\ & A &=& ( 2\pi r ) \cdot h + ( 2\pi R ) \cdot h + 2\pi R^2 - 2\pi r^2 \\ & A &=& 2\pi ( r \cdot h + R \cdot h + R^2 - r^2 ) \\ & A &=& 2\pi [ h(r + R) + R^2 - r^2 ] \qquad & | \qquad R^2 - r^2 = ( R + r )(R - r)\\ & A &=& 2\pi [ h(r + R) + ( R + r )(R - r) ] \\ & A &=& 2\pi [ h(r + R) + ( r + R )(R - r) ] \\ & A &=& 2\pi (r + R)( h + R - r ) \\\\ & \mathbf{ A }& \mathbf{=} & \mathbf{ 2\cdot (r + R)\cdot ( h + R - r )\cdot \pi } \\ \end{array}\)

\(\begin{array}{lrcll} & A & = & 2\cdot (r + R)\cdot ( h + R - r )\cdot \pi \qquad r = 3\ mm \qquad R = 6\ mm \qquad h = 18\ mm \\ & A & = & 2\cdot (3 + 6)\cdot ( 18 + 6 - 3 )\cdot \pi \\ & A & = & 2\cdot 9\cdot 21 \cdot \pi \ mm^2 \\ & A & = & 378\cdot \pi \ mm^2 \\ & A & = & 1187.52202306 \ mm^2 \\ & \mathbf{A} & \mathbf{ = } & \mathbf{1187.52 \ mm^2 \qquad (\text{ rounded to the nearest hundredth}) }\\ \end{array}\)

or

\(\begin{array}{lrcll} & A & = & 1187.52202306 \ mm^2 \cdot \frac{1\ cm}{10\ mm} \cdot \frac{1\ cm}{10\ mm} \\ & A & = & \frac{1187.52202306}{100} \ cm^2 \\ & A & = & 11.8752202306 \ cm^2 \\ & A & = & 11.8752 \ cm^2 \\ \end{array}\)

Or kilograms, and tenths of kilograms.

The sine of an angle only takes on values from -1 to + 1   ....so.....sin(alpha)  = 78   is impossible

Note, Yura_chan......

t - 4     can be factored  as

(√(t)  - 2) (√(t)  + 2) 

Because

√(t) * √(t)   - 2√(t)  + 2√(t)  (-2)*(+2)   =

t  -  4

Find the savings plan balance after 2 years with an APR of 3​% and monthly payments of ​$300

The balance of the savings plan after 2 years will be=$7,410.85 @ 3% compounded monthly.

The balance of the savings plan after 2 years will be=$7,407.95 @ 3% compounded annually.

The formula you use to calculate this is:FV=P{[1 + R]^N - 1/ R}=FV OF $1 PER PERIOD, Where R=Interest rate per period, N=number of periods, P=periodic payment, FV=Future value.

I still think Nauseated could do a better job with his usual great degree of humor, but he will come back, Nauseated is usually very busy, but we do sure enjoy it when he drops by ready to gives us a show, even if it means bad disadvantages for me

In part B, how did you split the bottom x-4 into (x+2)(x-2)

I thought you could only do that if it was (x-4)^2?

Thanks, TR.....I'll do it by substitution just so you can have two different methods to look at

4x-y=-5   →    y  = 4x + 5     (1)

-2x+3y=10   (2)

Substitute  (1)  into (2)  for y

-2x + 3(4x + 5)   = 10    simplify

-2x + 12x + 15  = 10

10x + 15  = 10      subtract 15 from both sides

10x  = -5           divide both sides by 1

x = -5/10  = -1/2

And using (1)    y = 4(-1/2)  + 5   =  -2 + 5   =  3

Thanks for that, TR.......couldn't have said it better, myself.....

It is easiest to do elimination

4x-y=-5

(-2x+3y=10)2

4x-y=-5

-4x+6y=20

5y=15

y=3

4x-1(3)=-5

4x-3=-5

   +3 +3

4x=-2

x=-1/2

answer: (-1/2, 3)

a.) t0 = 1

[f(t)- f(t0)] / [ t - t0 ] =  

[√(4t)  - √ (4*1)] / [t - 1]  =

[ √(4t) - √(4)] / [ t - 1]  =

[ 2 √(t) - 2] / [t - 1]  =

2 [√(t) - 1] / [t - 1]  =

2[√(t) - 1] / [ (√(t) - 1) (√(t) + 1) ]  =

2 / (√(t) + 1)                     

b.) t0= 4

[√(4t)  - √ (4*4)] / [t - 4] =

[ √(4t)  - √(16)] / [ t - 4] =

[ 2 √(t) - 4 /  [t - 4]  =

2 [√(t)  - 2] / [t - 4]  =

2 [√(t)  - 2] /   [ (√(t)  - 2) (√(t)  + 2) ] =

2 / (√(t)  + 2)   

Sounds like something really went down here, while I have been gone.

Because.

2x^2+3x-2  =  (2x - 1) (x  + 2)

Simplify the following:

(81 m^3-25 m)/(9 m+5)

Factor m out of 81 m^3-25 m:

m (81 m^2-25)/(9 m+5)

81 m^2-25 = (9 m)^2-5^2:

(m (9 m)^2-5^2)/(9 m+5)

Factor the difference of two squares. (9 m)^2-5^2 = (9 m-5) (9 m+5):

(m (9 m-5) (9 m+5))/(9 m+5)

Combine powers. (m (9 m-5) (9 m+5))/(9 m+5) = m (9 m-5) (9 m+5)^(1-1):

m (9 m+5)^1-1 (9 m-5)

1-1 = 0:

m (9 m-5) (9 m+5)^0

(9 m+5)^0 = 1:

Answer: |m(9m - 5)

First you'd want to simply the numerator, 

Factor m out of \(81m^3−25m. \)

Which results in \(\frac{m(81m^2−25)}{9m+5 }\)

Given that the Co-Efficent is 81, the pronumeral (m) is sqaured and 25 is also a Sqaure Number, you may Square Root all of the numerator to produce this: \(\frac{m((9m)^2−5^2)}{9m+5}\)

Factor using the difference of squares. 

Producing: \(\frac{m(9m+5)(9m−5)}{9m+5 }\)

Reduce the expression by cancelling the common factors. (See the denominator, [9m+5] and the numerator [m(9m+5)]

\(m(9m−5) \)

Apply the distributive property. 

\(m(9m)+m(−5)\)

Simplify

\(9m^2+(−5m)\)

A Note of Caution here, Make sure you understand that a Positive and a Negative form a NEGATIVE:

\(9m^2−\Leftarrow5m\)

Ignore the Arrow, it is just a means of Bolding or Stating something worth noting.

\(9m^2−5m\)

is your Answer.

its 15

The answer is 20.5