Ok so to start you plug in what’s in the parentheses for x
4c=8-5(4c)
2-k=8-5(2-k)
4p+3=8-5(4p+3)
In the first one you distribute the -5
4c=8-20c
Then add 20c to both sides
24c=8
And divide by 24
C=8/24 or 1/3
Distributing the -5 on the second one gets you
2-k=8-10+5k
Then you combine like terms
2-k=-2+5k
Subtract 5k from both sides
2-6k=-2
Subtract 2 from both sides
-6k=-4
Divide by -6
K=4/6 or 2/3
and lastly the equation is 4p+3=8-5(4p+3)
So you distribute -5
4p+3=8-20p-15
Combine like terms
4p+3=-20p-7
Add 20p to both sides
24p+3=-7
Subtract 3 from both sides
24p=-10
And then divide by 24
P= -10/24 or -5/12
Answer:
B
Step-by-step explanation:
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%
