Let, x b hrs truck drove. so in x hrs, truck covered: 45*x miles
since car drove 2 hrs less than x, car covered: 60* (x-2) miles

as u mentioned, both covered equal distance:
45*x=60* (x-2)
ie, x = 8 hrs
x-2 = 6 hrs
miles covered = 6*60 or 8*45 = 360 miles