Answer:
PQ measures 36 units.
Explanation:
Line RS bisects segment PQ at R. By the definition of a bisector:
![\displaystyle PR = RQ](https://img.qammunity.org/2022/formulas/mathematics/high-school/gae4dre02mpq3217bbe2x4w1b5ody3vyos.png)
Hence:
We are given that RQ = x + 9 and RP = 2x, and we want to determine PQ.
Solve for x. Substitute:
![\displaystyle (2x) = (x+9)](https://img.qammunity.org/2022/formulas/mathematics/high-school/jspml2axak22q1c2st34u3sio6cf0xxz0f.png)
Hence:
![\displaystyle x = 9](https://img.qammunity.org/2022/formulas/mathematics/high-school/gkls7dvix1ctvz1bru48mho4lcmvrx97f2.png)
PQ is given by:
![\displaystyle PQ = PR + RQ](https://img.qammunity.org/2022/formulas/mathematics/high-school/80qxsy7em059choqnnmskp3ta2jhle9lwp.png)
Since PR = RQ:
![\displaystyle PQ =2PR](https://img.qammunity.org/2022/formulas/mathematics/high-school/n0euhg6761o2anpxmeu07fqxkrnf9peg6w.png)
Substitute and evaluate:
![\displaystyle \begin{aligned} PQ &= 2PR \\ &= 2(2x) \\ &= 4x \\ &= 4(9) \\ &= 36 \end{aligned}](https://img.qammunity.org/2022/formulas/mathematics/high-school/qpk0wy8c13gnduk8mwgexiuj2s4318e0p0.png)
Hence, PQ measures 36 units.