9x +y=-5
Coefficient of x

x=-14y

Step-by-step explanation:

9x+y=-5

x+y=-5-9

x+y=-14

x=-14y

1).  $2,700 is  (2,700/6,000) = 45% of  6,000.

      It took 6 years to earn it, so it earned (45%/6) = 7.5% each year.
      That's the simple-interest rate.


2).  The investment earns 4.5% each year, so it earned 9% in 2 years.

      The $1,150.65 is the 9% of the original investment.  Call it V.

      1150.65 = 0.09 x V .

Divide each side by 0.09 :

         V  =  1150.65 / 0.09  =  $12,785 .


3).  There are 18 marbles in the bag all together.

a).  8 of them are green.  If you close your eyes and pull out 1 marble,
the probability that it's a green one is
                                                               8/18 = 4/9  =  44.4% .

b).  If it was a red marble, and you put it in your pocket, then
there are only 17 in the bag now, and 8 of them are still green.

If you pull another one, the probability that it's green is

                                                               8/17  =  47.1% .


5).  There are 10 marbles in the bag all together.
(The second sentence doesn't say anything, and doesn't mean anything.)

If you pull out a silver marble and put it in your pocket, then
there are 9 marbles in the bag, and 2 of them are orange.

The probability of pulling an orange marble now is

                                  2/9  =  22.2% .