Lead rod and glass rod have same length at 20.8 degrees celcius. The lead rod is heated to 53.4 degrees celcius. At what temperature must the glass be heated so they are the same length? I know that (change in L)/Lo = (alpha)(change in Temperature) but im not sure how to set (change in L of lead) = (change in L of glass) and i dont know what variables to use to solve for T of glass. Can anyone help me get started on this one. Much appreciated!!