ANSWER:
2(-x+6)
If you want it simplified the answer is 2x+12
Hopefully I helped
let the consecutive multiples be 7(n-1) , 7n and 7(n+1)
so 7(n-1)+7n+7(n+1)=777
or 3n=111,
n=37
252,259,266
Wouldn't it be. 8 pieces because you cut each sides into two pieces so like this. —|—. You'll end up having four square pieces, but count the pieces that creates an L shape.
best wishes good luck