Answer:
Explanation:
Your total spent is $15
Your friend spent $3 more than you, this is represented by 3+x.
You spent an unknown amount of money, this is represented by x.
So, your equation is 15=3+x+x.
This becomes 15=3+2x.
You then subtract 3 to the other side to get.
12=2x
Then divide 12 by 2, in order to leave variable "x" by itself.
6=x is the amount you spent on lunch.
Your friend spent $3 more so add $3 to the amount you spent to get...
$9 spent by your friend.
You=$6
Friend=$9
Total=$15
To prove the solution is correct, plug 6 in for x.
15=3+2(6)
15=3+12
15=15 thus proving the solution is correct.