Answer:
[tex]k=\frac{2P}{x^{2}}[/tex]
Step-by-step explanation:
The question is
Which equation should she use?
we have the formula
[tex]P=\frac{1}{2}kx^{2}[/tex]
Solve for k
That means ----> isolate the variable k
Multiply by 2 both sides
[tex]2P=kx^{2}[/tex]
Divide by x^2 both sides
[tex]\frac{2P}{x^{2}}=k[/tex]
Rewrite
[tex]k=\frac{2P}{x^{2}}[/tex]