Hey there!
Here's your answer: the perimeter of the redone yard would be ~193 feet
Hope this helps!
It’s really hard to see the picture
Well what i think you're asking here...I apologie if I'm wrong but what I did was
f(-1) = 4 * 7^t = 4/7
and
f(2) = 4 * 7^t = 196.
Is this what you wanted if not I can...try another way.
If you evaluate directly this function at x=0, you'll see that you have a zero denominator.
Nevertheless, the only way for a fraction to equal zero is to have a zero numerator, i.e.

So, this function can't have zeroes, because the only point that would annihilate the numerator would annihilate the denominator as well.
Moreover, we have

So, we can't even extend with continuity this function in such a way that 