Question

help!
The Flat Rock auto assembly plant in Detroit, Michigan, produces three different makes of automobiles. In two years, the plant constructed a total of 390,000 cars. If 90,000 more cars were made in the first year than in the second year, how many cars were made in each year?

Answer 1

let's say they made x in the first year and y in the second year...

Answer 2

\[\large x+y=390,000\]
...correct?

Answer 3

and we also know:\[x=90,000+y\]


substitute this in the first equation:\[(90,000+y)+y=390,000\]

and then solve for y ... and then get x

Answer 4

so x would be 180,000, right?

Answer 5

Right

Answer 6

\[90,000+2y=390,000\]

Answer 7

\[2y=300,000\]

Answer 8

\[y=150,000\]

Answer 9

\[x=90,000+150,000\]

Answer 10

\[x=240,000\]