Question

To what Celsius temperature must 44.5 mL of methane gas at 43.0°C be changed so the volume will be 63.0 mL? Assume the pressure and the amount of gas are held constant.

I have already tried T1V1=T2V2

Answer 1

And I'll bet you didn't get the right answer. It's
V1/T1 = V2/T2
And don't forget to change T to Kelvin.