Explanation:
B.
if he is just talking about the length than it is,
4(13x + 8)
of he is talking about overall length he swam than,
4(13x + 8) + 3(7x - 2)
c.
if x = 12
than
perimeter = 2l + 2b
so, after inserting the values we got,
→ 2[13(12) + 8] + 2[7(12) - 2]
→ 2 (156 + 8) + 2(84 - 2)
→ 2 × 164 + 2 × 82
→ 328 + 164
→ 492 ft. ← perimeter
and yeah, according to me
a is wrong as,
formula of perimeter = 2l + 2b or 2(l+b)
so, the answer should be,
2(13x + 8) + 2(7x - 2) or 2 [ (13x + 8) + (7x - 2)
hope this answer helps you dear...take care and may u have a great day ahead!