The developers of a web site are tracking its number of adult users and teenage users. They found that the equation 48x + y = 729 models the number of teenage users over time, and the equation 135x − 2y = −140 models the number of adult users over time. In both equations, x is the number of years since 2000, and y is the number of users in thousands. During what year was the number of teenage users and adult users the same?

So the year when both the amount of users were the same can be found by using the both equations to solve for x  (since y is the same)

48x + y = 729

we will take the value of y from this equation and use it in the other equation

y = 729 - 48x

135x - 2y = -140

135x - 2(729 - 48x) = -140

135x -1458 + 98x = -140

231x = 1318

x = 1318/231

x = 5.7 years after 2000

it is 28 degrees colder in detroit than philadelphia.

step-by-step explanation:

what number adds to 21

-7 + ? = 21

-7 + 28 = 21

hope it