The potential energy, P, in a spring is represented using the formula P = A equals StartFraction one-half EndFraction b h. kx2. Lupe uses an equivalent equation, which is solved for k, to determine the answers to her homework. Which equation should she use?

k = 2Px2
k = k equals StartFraction one-half EndFraction P x squared. Px2
k = k equals StartFraction 2 P Over x squared EndFraction.
k = k equals StartFraction P Over 2 x squared EndFraction.