Jake bought 9 drinks for everyone in his family. He

bought larges and smalls. The larges cost $1.50 and

the smalls cost $.90. He spent $10.50 in all. How

many larges (L) and how many smalls (s) did he

buy?

L + s = 9

1.5L +.9s = 10.5

Step-by-step explanation:

It looks like your 2 equations are already there for you, so that's good! Now we just need to solve this system by either substitution or elimination to find the number of small drinks, s, and large drinks, L. I chose to solve the first equation for L and then sub that value into the second equation.

If L + s = 9, then L = 9 - s. I'll sub that into the second equation now for L:

1.5 (9 - s) +.9s = 10.5 and

13.5 - 1.5s +.9s = 10.5 and

-.6s = - 3 so

s = 5

There were 5 small drinks bought and 4 large drinks bought.