Answer:
![x=\sqrt{v^2 -(2k)/(m)}](https://img.qammunity.org/2021/formulas/physics/high-school/6jb43e9jpmjbyev10co0w589b3t1tbpbtr.png)
Step-by-step explanation:
Equation Solving
The procedure to solve an equation consists in trying to isolate the required variable by applying algebra and / or elemental properties of some functions. If not possible, then we could use formulas or iterative approaches.
The equation to solve is
![\displaystyle k=(1)/(2)mv^2 -(1)/(2) mx^2](https://img.qammunity.org/2021/formulas/physics/high-school/63kvp1jc68nmb2cfteqd6unb55cdd0ubfw.png)
Rearranging
![\displaystyle (1)/(2) mx^2=(1)/(2)mv^2 -k](https://img.qammunity.org/2021/formulas/physics/high-school/n4g4vhvcaadgrh1659gsatdxcktusl6rc6.png)
Multiplying by 2/m
![\displaystyle x^2=v^2 -(2k)/(m)](https://img.qammunity.org/2021/formulas/physics/high-school/bkt0ymuhwh1vjnz8z63kp4h6rfnha8yfnc.png)
Solving for x
![\displaystyle \boxed{x=\sqrt{v^2 -(2k)/(m)}}](https://img.qammunity.org/2021/formulas/physics/high-school/ewyy75y25jigh57asko878z2xhna2njlrp.png)