i cannot figure out how to go from not knowing L and T to findingout T after i s

Question

i cannot figure out how to go from not knowing L and T to findingout T after i set up my solution.

A person bending forward to lift a load "with his back" shown inFigure (a) rather than "with his knees" can be injured by largeforces exerted on the muscles and vertebrae. The spine pivotsmainly at the fifth lumbar vertebra, with the principal supportingforce provided by the erector spinalis muscle in the back. To seethe magnitude of the forces involved, and to understand why backproblems are common among humans, consider the model shown in Fig.(b) of a person bending forward to lift a Wo =195 N object. The spine and upper body arerepresented as a uniform horizontal rod of weightWb = 340 N, pivoted atthe base of the spine. The erector spinalis muscle, attached at apoint two-thirds of the way up the spine, maintains the position ofthe back. The angle between the spine and this muscle is 12.0°.Find the tension in the back muscle and the compressional force inthe spine.
im stuck here

-(L/2)*(340)-(L)*(195)+(2/3)*(LTsin12) = 0

how do i find T?

Explanation / Answer

Here :              -(L/2)*(340) - (L)*(195) + (2/3)*(LTsin12) = 0
                  Taking L common and taking it into right hand side weget ,                 - ( 340 / 2 ) - 195 + (2/3) * (T sin 12 ) = 0                     - 365   +     (2/3) * (Tsin 12 )   = 0                                (2/3)* (T sin 12 )    = 365                                           (Tsin 12 )    =   365 * (3/2)                                                T           =   547.5 / sin12   = 2.633 x 103   N Hope this helps u!

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