Question 21380
1.  -3y(3y-3) - 2y = 8
-9y^2 + 9y -2y = 8
9y^2 - 7y +8 = 0  representing ax^2 + bx + c = 0,
using the quadratic equation (-b +- (b^2 - 4ac)^1/2 )/2a
y = (7+-(49-4(9)(8))^1/2 )/18
y = (7+-(-239)^1/2 )/18
y = (7+-i(239)^1/2 )/18
y = 0.38888 +- 0.8589i
are you sure you have the equation correct?

2. 6-5S/3 = S
6 = S +5S/3
6 = (8/3)S
S = 9/4

3.  5(1-X)/6 = -X
(5-5D)/6 = -X
5-5X = -6X
X = -5

4. 2 is the answer, then
2/a + 1 + 4 = 10/a + 1
2/2 + 1 + 4 = 10/2 + 1
1 + 1 + 4 = 5 + 1
6 = 6

5.  Let X = Speed of one train, X+10 = Speed of 2nd train.
    Let t = time
Then 200 miles = Xt + (X+10)t
If they traveled for t=2 hours
200 = 2X + 2(X+10)
200 = 4X + 20
4X = 180
X = 45 mph for 1st Train
and X+10 = 55 mph for 2nd Train

6.  Let D = # dimes, Q = # Quarters
D = 2Q + 2
.10D + .25Q = 4.25
Subsitute D = 2Q + 2 into 2nd equation yields
.2Q + .2 + .25Q = 4.25
.45Q = 4.05
Q = 9 quarters
Then D = 2x9 + 2 = 20 Dimes

You'll ace the test now.