Question

The developers of a web site are tracking its number of adult users and teenage users. They found that the equation

56x + y = 737
models the number of teenage users over time, and the equation
121x − 2y = −238
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?

Answer 1

X=5.7 after the years

Answer 2

x = 5.7 years after 2000

Explanation:

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