Answer:
3,662
Step-by-step explanation:
It says that x= -10 so you have to multiply 345 by -10 because x is next to the number 345. Then you get the number -3450-212 from there you can see they are both negative so you can add them together and take out the negative symbol at the end. Hope that helped!

now, notice, we use the decimal format for the percent, namely 17% is 17/100 or 0.17 and so on
so.... we know, whatever "x" and "y" is, they must add up to 100 grams
thus x + y = 100
and whatever the concentrated amount is, it must add up to 17 grams for the composition
thus 0.1x + 0.2y = 17

solve for "x", to see how much is needed of the 10% alloy
what about "y"? well, y = 100 - x