George and carmen went on a bicycle trip. they took a bus to their starting piont, and then biked the rest. they traveled 275 kilometers in totals, and they biked 55 kilometers more than they were bussed.
x=kilometers travel by bike and y= kilometers
find how many kilometers they traveled by bike

We need to do a system of equations here.

x + y = 275 (if you travel x km by bike and y km by bus, then you travel 275 km as given in the problem)
y = x + 55 (the problem stated that they were bussed (y) the amount they biked plus 55 more km (x + 55))

The second equation is already solved for y. So, we can plug it in to the first equation.

x + (x + 55) = 275
2x + 55 = 275 [combine x terms]
2x = 220 [subtract 55 from both sides]
x = 110 [divide by 2 to isolate x and solve for it]

Now we know that x is 110, the distance they traveled by bike.
And that's what we needed to answer the problem!