You sell small candles ($3 each) and large candles ($5 each) at a craft fair. You collect $84 selling a total of 20 candles. Write a system of equations to represent this scenario and solve it by substitution. How many small candles did you sell? How many large candles did you sell? PLEASE HELP

Mexico city, mexico, is the world's second largest metropolis and is also one of its fastest-growing cities with a projected growth rate of 3.2% per year. its population in 1991 was 20,899,000 people. use the formula p = 20.899e0.032t to predict its population p in millions with t equal to the number of years after 1991. what is the predicted population to the nearest thousand of mexico city for the year 2010?

For the equations below which statement is true ?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15