Answer:
17/400
Step-by-step explanation:
.0425 = 425/10,000
this can be simplified to be 17/400
To solve these problems you need to use the quadratic formula which is listed below.

So, if you take #2.
The

has a 1 in front of it. The x has a -3 in front of it. The last number is also -3. So:
a = 1
b = -3
c = -3
Then you can plug all of these into the equation and simplify. Which gives you:
I think it’s b but I’m not to sure sorry if it’s wrong!
Answer:
Step-by-step explanation:
Assume that the amount needed from the 5% acid is x and that the amount needed from the 6.5% acid is y.
We are given that:
The volume of the final solution is 200 ml
This means that:
x + y = 200
This can be rewritten as:
x = 200 - y .......> equation I
We are also given that:
The concentration of the final solution is 6%
This means that:
5%x + 6.5%y = 6% (x+y)
This can be rewritten as:
0.05 x + 0.065 y = 0.06 (x+y) ............> equation II
Substitute with equation I in equation II and solve for y as follows:
0.05 x + 0.065 y = 0.06 (x+y)
0.05 (200-y) + 0.065 y = 0.06 (200-y+y)
10 - 0.05 y + 0.065 y = 12
0.015y = 12-10 = 2
y = 2/0.015
y = 133.3334 ml
Substitute with the y in equation I to get the x as follows:
x = 200 - y
x = 200 - 133.3334
x = 66.6667 ml
Based on the above calculations:
The amount required from the 5% acid = x = 66.6667 ml
The amount required from the 6.5% acid = y = 133.3334 ml