What does it mean for an ordered pair to be a solution to a system of equations?

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?

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

Which part of a 2-column proof is the hypothesis of the conjecture? a) given b) reasons c) prove d) statements ! i think it's b but i'm not quite