Answer:
the third : x + x + x + 2 = 10
Explanation:
x = the length of the first 2 pieces.
the third piece will be x+2 ft long.
so, the total length of the original board is the sum of all 3 pieces and must be all in all 10 ft.
10 = x + x + (x + 2) = x + x + x + 2
so, it is the third answer option.