Let
f(x) = -x-3 if x <= -7
f(x) = 2x + 1 if x > -7
Find the sum of all values of $x$ such that f(x) = 0.
Suppose x <= -7. When f(x) = 0, -x - 3 = 0. This means x = -3, which is not <= -7. This root is rejected.
Suppose x > -7. When f(x) = 0, 2x + 1 = 0. This means \(x = -\dfrac{\boxed{\phantom{\text{aaaaa}}}}{\boxed{\phantom{\text{aaaaa}}}}\).
Therefore, the sum of all values of x such that f(x) = 0 is \(-\dfrac{\boxed{\phantom{\text{aaaaa}}}}{\boxed{\phantom{\text{aaaaa}}}}\), as it is the only solution to f(x) = 0.
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