Well since you're using 3/8 and you need to make 4 batches, you need to multiply 3/8 with 4 it would equal 12/8 or 1 4/8 (I could be wrong but this is my answer hopefully this helps) :) <span />
Answer: 
Step-by-step explanation:
We know that the standard quadratic equation is ax^2+bx+c=0
Let's compare all the given equation to it and , find discriminant.
1. a=2, b= -7, c=-9
So it has 2 real number solutions.
2. a=1, b=-4, c=4

So it has only 1 real number solution.
3. a=4, b=-3, c=-1

So it has 2 real number solutions.
4. a=1, b=-2, c=-8
So it has 2 real number solutions.
5. a=3, b=5, c=3

Thus it does not has real solutions.
The points are at (8,0) and (0,6)
10 I think because 10+10+8+8=36 and 8 is 2 less than 10