she should add 7 liters of 10% acid solution
Explanation
Step 1
set the equation:
a) let X represents the amount os solution that is 4% acid
let Y represents the amount os solution that is 10% acid
so
I)

if he has 14 liters of 4% acid solution


Step 2
solve the equation :

therefore,
she should add 7 liters of 10% acid solution
I hope this helps you
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Answer: 12(5x - y)
Step-by-step explanation:
Answer:
75
Step-by-step explanation:
Belle got it wrong when she added the 9 because it was already positive, meaning she would’ve subtracted it.