Your answer is 84 meters.
We can call the width x, and thus the length 5x, and then we can say that 5x × x = 245, which simplifies to 5x² = 245, and then we can solve:
5x² = 245
÷ 5
x² = 49
√
x = 7
Now that we know what x is, we can find the perimeter by using it as the width, and then multiplying it by 5 to find its length. This gives us:
(7 × 2) + (5 × 7 × 2) = 14 + (35 × 2) = 14 + 70 = 84
So your answer is 84 meters.
I hope this helps!
