ElectricPavlov

 a      b      and    1000-a-b    are the amounts   

2a   + 2b   + (1000-a-b -100)  = 1500

a + b  + 900 = 1500

a + b = 600

1000 - (a+b)  =   400    is what Al had  

a = k / b

-3 = k / -6

k = proportionality constant = 18

a = 18/b

a = 18/8 = 2 1/4     or   9/4

7x^2 + 5x - h = 0      for only ONE solution, the discriminant must = 0

b^2 - 4ac  = 0

5^2 - 4(7)(-h)

25 + 28 h = 0

h = -25/28

Ways to roll a sum of '6'  with two rolls

1 5

5 1

2 4

4 2

3 3       1 out of 5       =    1/5

Here is  A  way to solve first one....may not be THE BEST way....

     circle radius = sqrt 60

draw a line from origin to corne of square that touches circle     this line forms a   arc tan (1/3) = 18.435  degree angle

     sqrt 60 cos 18.435   = length of 3 boxes = 7.34      so each square is side length   7.34/3

              then total area of  1 square   =     (7.34/3  *  7.34/3) =  6 in²    

All of the equations in a system true.

Perhaps the THIRD   fifth and ninth would be a r = 2

x > 2      Answer A B and C

y>0                         B and C

x+y<5       Answer B

x = salary before increase

1.16 x = 55680

x = 55680/(1.16) =  $ 48000.

Ursala  Andre(ss) .... I wonder if that was a joke?

Anyway .    Andre(ss) has a 1 minute head start    =   48 meters ahead

 Ursala swims 60-48 = 12 meters/min  faster than Andre(ss) 

      Ursala will close that  48 -30 = 18  meters in   18 m / 12 m/s = 1  1/2  minutes to be 30 m behind Andre(ss)