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Dragan, your answer is mathematically correct, but the problem specified to put the answer in simplest radical form.  Apparently you don't know what that means, so I recommend that you look it up with google for a full explanation. 

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If y9ou let the width of the entrance be   a+b   separated like this.

then it is quite easy to get 'b' in terms of 'a' using similar triangles.

After that it is easy to get a value of h.

See if you can do it now  

Gentle hint: Next time say what you can or cannot do right at the start.  Talk about your question a little.

If you had stated that you had thought about it but you did not understand what the picture would look like in the beginning then I would not have wasted your time by asking you to present a picture.    :)

George can mow his lawn in 3 hours, Al can mow his lawn in 5 hours.  How long will it take both of them working together? 

We're assuming George's lawn and Al's lawn are the same size, to make 

the rates consistent, and that they're working together on the same lawn. 

George's rate of mowing is 1 lawn per 3 hours, which is 1/3 lawn/hour. 

Al's          rate of mowing is 1 lawn per 5 hours, which is 1/5 lawn/hour. 

Working together means add the two rates    1/3 + 1/5  =  combined rate of mowing 

After finding common denominator                5/15 + 3/15  =  8/15     They can mow 8 lawns in 15 hours. 

So 8/15 lawns per hour ... invert that amount to get the value in units of hours per lawn 

15/8 hours per lawn, which when you do the division is 1.875 hrs/lawn,

or another way of saying it is:  one hour, fifty-two & a half minutes. 

_.

This is how I interpreted the question.

1/3   +   1/5     =    1/B       B is the time for Both working (in hours)   Solve for B

So we know that it spreads 25 square meters every 1/6 of an hour. That's 10 minutes.

So 25 meters PER 10 minutes.

2 hours = 120 minutes.

120 / 10 = 12.

25 * 12 = 300 meters.

I cannot tell you how much area it COVERS, but I can tell you how much it has SPREAD:

25 m² /  1/6 hr   =  150 m²  / hr

150 m²  / hr      *    2 hr   =   300 m²

Line 1 has the equation of 3x+4y = -14. I'm going to change this into slope intercept form

4y = -14 - 3x

y = -3x/4 - 7/2 This shows that the slope is -3/4. A  function perpendicular to this would have a slope of 4/3. For 2 linear functions to be perpendicular their slopes must be negative reciprocals. 

So line 2 so far has the equation y = 4x/3 + b

The question gives that this function passes through point -5,7, and we can plug this into the equation

7 = 4(-5)/3 + b

7 = -20/3 + b

b = 7 + 20/3

b = 21/3 + 20/3

b = 41/3

The question is asking for m + b

m = 4/3 and b = 41/3

m + b = 4/3 + 41/3 = 45/3

m + b = 15

are the ropes on the pole?

A bag of coins contains 2 quarters, 5 dimes, 3 nickels, and 4 pennies. If 2 coins are randomly chosen from the bag, one after the other, and not replaced, and if the total value of the chosen coins is 26 cents, what is the probability that a third coin randomly chosen from the bag will be a penny? 

You're starting with 2 + 5 + 3 + 4 coins for a total of 14 coins. 

There's only one way to make 26¢ with 2 coins, and that's a quarter and a penny. 

So remaining in the bag are 1 + 5 + 3 + 3 coins for at total of 12 coins. 

3 of those 12 coins are pennies, so the likelihood of randomly pulling a penny 

is now 3 out of 12, this fraction reduces to 1 out of 4, so the answer is  B. 1/4 

Thnx, Alan!  I should have known that !    A temp brain infarct !

ok thx

Success:  p = 0.75

Fail:  q = 1 - p  = 0.25

a)  Prob of missing all 10 shots = q¹⁰ ≈ 9.5*10^-7

b) Prob of at least one success = 1 - prob of no successes = 1 - q¹⁰.

Since all cross-sections of a sphere are circles we can use the fact that  r² = 4*(16 - 4)  where r is the radius of the circular water surface.

So r = sqrt(48) = 4sqrt(3) m. Hence diameter = 8sqrt(3) m

You can also do this as follows:

Isolate y in 3x + 4y = -14 ==> y = 3x/4 - 14/4

Slope of Perpendicular = -4/3, point-slope form of equation y - 7 = -4/3(x + 5)

==> 3y - 21 = -4(x + 5) = -4x + 20

==> 3y = -4x + 41

==> y = -4/3*x + 41/3

m + b = -4/3 + 41/3 = 37/3

Their combined speeds, (x)   and (x-30)   cover the 390 km in 3 hours

3 hours  *   x  km/hr       +      3 hours * (x-30)km/hr     =     390 km

3x                                    +    3 (x-30)                          = 390

solve for 'x'  the speed of the express, then ffreight = (x-30)    

EP, as a terawatt is a unit of power, then 180000 of them reaching the Earth would mean there are 180000 teraJoules of energy reaching the Earth every second.

thank you!

sum of ingredients = sum of the products

.18 x           +     .4 (10 - x)         =   .20 (10)        solve for 'x' the liters of 18%      then   40 % will be 10 -x   liters  

Need to know this:

A total of about 180,000 terawatts of solar power reaches Earths surface     ....   Per year?   per day?   per hour?   per second??????

90x         +     40 ( 50 - x )    =  85 ( 50)      solve for x the amount of 90 cent pounds, then 50 - x  is the amount of 40 cent pounds.

Choose  2 preshmen out of 5   =     5 c 2  = 10      x

              3 soph out of  7                 7 c 3   = 35     x

               4 jun               8                8 c 4 =   70     x  

               5 seniors        9                9 c 5  = 126

10  x  35   x   70   x   126    =.......  

Expand a(x+p)² + q as  ax² + 2apx + ap² + q

Compare with 3x² + 2.4x term by term:

x² term:  a = 3

x term:  2ap = 2.4

constant term: ap² + q = 0

Use these three equations to find a, p and q.