Answer:
6
Step-by-step explanation:
cancel out 5 by multiplying its by 5, what you do to one side you do to the other. so you also multiply 12 by 5. and you should get 60
Answer:
$31.56
Step-by-step explanation:
$9.85 × 4 = $39.40
$39.40 25% off is $29.55
6.75% rounded to the nearest cent 6.80%
Sales tax is $2.01
$29.55 + $2.01 = $31.56
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
When solving equilibrium problems a quadratic results it has the general form 0 equals x ^ 2 + BX + C a b and c may be positive or negative numbers usually when the wrong answer is plugged in it will lead to a negative concentration or amount. good luck