If x-2y=0 and 3x+y=7 whats the vaule of ×?

How do you determine if an ordered pair is a solution to a given equation?

How many liters of peroxide should be added to 12 liters of an 8% peroxide solution so that the resulting solution contains 16% peroxide?   original added new amount of peroxide 0.96 liters x 0.96 + x amount of solution 12 liters x 12 + x 0.18 liter 1.14 liters 1.92 liters 2.10 liters

Tim tradesman pays $2,000 annually for $125,000 worth of life insurance. what is the cash value of the policy after 10 years? 11,125 13,125 17,800 111,250