Answer:
B
Step-by-step explanation:
Step-by-step explanation:
If x is the volume of pure water:
Initial + added = final
0.95 (840) + 0 (x) = 0.70 (840 + x)
798 = 588 + 0.70 x
x = 300
840 + x = 1140
You need to add 300 mL of pure water to obtain 1140 mL of the desired 70% solution.
D. 25% as there are 8 sections and two wanted outcomes this can be simplified into a 1/4 so 1/4=25%
Answer:
A) x = 2, x = 7
Step-by-step explanation:
x^2 + 14 = 9x
Subtract 9x from each side
x^2-9x + 14 = 9x-9x
x^2-9x + 14 = 0
What 2 numbers multiply to 14 and add to -9
-7*-2 = 14
-7+-2 = -9
(x-7)(x-2) = 0
Using the zero product property
x-7 = 0 x-2 =0
x=7 x=2