How would I solve for Length? simple math equation involving sin/cosine?

[jcfor3ver]

Homework Statement

How would I solve for L in this expression:

sintheta=L/sq.rt(x^2+L^2) ?

Homework Equations

sintheta=L/sq.rt(x^2+L^2) ?

The Attempt at a Solution

and if they have the same angle between them would solving for L create an equal answer using:
costheta=L/sq.rt(x^2+L^2)
??

given there is a 90 degree angle between the y and x axis, but the angle is unknown, but these two equations involve the same triangle.

Solving I received sq.rt((-x^2+(costheta/x))^2)=L but i think its wrong

 

[Mentallic]

Try squaring both sides, rearranging a bit and then factoring out L. You'll have an answer in terms of x and \theta