Feedback loop and Impulse Functions. How to find the response?

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This is my system. We know that h1(t) = δ(t-1) and h2(t) = δ(t+1).

Now my problem is how to find y(t). I know that the exit of the adder will give us

y1{t} = x(t) - h2(t) correct?

That means that y(t) = h1 * y1{t} = δ(t-1)*x(t) - δ(t+1)*δ(t-1) = x(t-1) - δ(t).

However, I don't seem to understand how to draw the unit step response of y(t).

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When setting up equations for a feedback loop, I usually start at the output and follow the path around once to see what happens to it.

If I start at $y(t)$, I go through the bottom block and get $y(t)*\delta(t+1)$, which yields $y(t+1)$.

Then I get to the summation block, and out pops $x(t)-y(t+1)$.

This signal then goes through the top block, becoming $\left[x(t)-y(t+1)\right]*\delta(t-1)=x(t-1)-y(t)$.

The signal that pops out of the top block is the output $y(t)$, so we can set up the equation:

$y(t)=x(t-1)-y(t)$.

Solving for y(t) gives: $y(t)=\frac{1}{2}x(t-1)$.