Step 1: Write the condition of equidistance.
\[
QP = QR
\]
Using the distance formula,
\[
\sqrt{(0-5)^2 + (1-(-3))^2} = \sqrt{(0-x)^2 + (1-6)^2}.
\]
Step 2: Simplify both sides.
Left side: $(0-5)^2 = 25$, $(1+3)^2 = 16$
\[
QP = \sqrt{25+16} = \sqrt{41}.
\]
Right side: $(0-x)^2 = x^2$, $(1-6)^2 = 25$
\[
QR = \sqrt{x^2 + 25}.
\]
Step 3: Equating and solving.
\[
\sqrt{41} = \sqrt{x^2 + 25} \ \Rightarrow\ 41 = x^2 + 25 \ \Rightarrow\ x^2 = 16.
\]
\[
x = \pm 4.
\]
Conclusion:
The values of $x$ are $4$ and $-4$.
$PQ$ is a chord of length $4\ \text{cm}$ of a circle of radius $2.5\ \text{cm}$. The tangents at $P$ and $Q$ intersect at a point $T$. Find the length of $TP$.