Answer:
90 g of water should be added and he will make 900 g of solution.
Step-by-step explanation:
Let x g be the amount of salt Ilya add to 810g of water to make 10% solution. Then 810+x g is the amount of new solution. Thus,
810+x - 100%,
x - 10%.
Mathematically,
So 90 g of water should be added and he will make 810+90=900 g of solution.
Answer:
x is equal to negative one, and y is equal to negative four.
Step-by-step explanation:
You can do this by solving one of the equations by either x or y, then substituting it into the other. Let's solve the second one for y:
Now we'll substitute that into the first equation:
So we now know that x is equal to -1. We can simply substitute that into one of the original equations to find y:
We now know that x is equal to -1, and y is equal to -4. We can also check our answer by plugging that -4 into the other equation, and see if we still get -1:
So we know that our answer is correct.