Answer:
Step-by-step explanation:
What we know is that A + S = 111. That is, the miles Andre drove plus the miles Scott drove totalled 111 miles. What we also know is that Scott drove quite a bit more than Andre did. Scott drove 7 miles more that ( +7 ) 3 times the number of miles Andrea drove. That looks like this algebraically:
S = 3A + 7
Now we can sub in that value for S to the original equation:
If A + S = 111 and S = 3A + 7, then
A + 3A + 7 = 111 and
4A + 7 = 111 and
4A = 104 so
A = 26 and
S = 3(26) + 7 so
S = 85 miles.
Scott drove 85 miles.
