어서 줄이다

cut it down, reduce it

줄이다 is deliberately making something smaller — a cost, a scope, a number — and the -아서/어서 says by what means: 같이 할 수 있는 부분 같이 해서 줄였다, 부동산으로 한정을 해서 줄여줬던, 도지를 통해서 줄이고 줄였기 때문에. Doubling it (줄여서 줄여서, 줄이고 줄였기) stresses cutting again and again. 줄다 is something shrinking by itself; 줄이다 is you shrinking it. Most of these lines are policy or business talk.

Register: mostly policy and business talk