Let x be the volume (liters) of pure (at 100%) acid needed
Let y be the volume (liters) of the other acid (at 10%) needed
The final solution will be:
a) x+ y = 63 liters, AND their respective concentration in acid: is
100% x & 10% :y that will generate 63 liters at 20%
b) x +0.1 y = 63x 0.2 = 12.6
Let's solve this system of 2 equations:
x + y =63
x + 0.1 y = 12.6
Solving it will give you:
x= 7 liters at 100%
y = 56 liters at 10%
So far your getting all of them right. But, maybe next time upload a better picture because it’s hard to see what you wrote.
Answer:
f(7) - f(-7)
= (4 - 7^2) - ((-7)^3 - 2*(-7))
= -45 - (-329)
= 284
Answer:
x = 2
Step-by-step explanation:
-5 This is the answer with the work
23
-28
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-5