There are two ways to solve the problem:
set up an equation that relates the two scores
Fabien had 7 points less than two times as many points as Carlos.
Fabien had 31 points.
Let C=Carlos' score
This means that
31 = 2C-7
Solve for C
2C=31+7=38
C=19.
So Carlos had 19 points.
Another way is to calculate the reverse operations in reverse order,
- -> +
x -> divide
Fabien had 7 points less (- -> +) than two times (x2 -> /2)as many points as Carlos.
So
C=(31+7)/2
=19 as above.
