Neither side could create any real openings, although Newcastle were beginning to force their opponents into making a few errors as the first half progressed at St James' Park.
Seven minutes before the interval City struck against the run of play, and it was Silva who made the breakthrough with a drilled finish past Krul following a flicked pass from Dzeko into his path.
There was an early scare for the Citizens in the second half as they struggled to deal with a corner whipped into the box, but the danger was soon cleared with their lead still intact.
Stevan Jovetic came close to adding a second for his side on 55 minutes when he struck the ball from 25-yards out, only to see his attempt fly wide of the target.
Another chance soon followed for City, this time for Dzeko who headed over from close range, while Yaya Toure's free kick sailed inches over the bar.
The missed opportunities almost proved costly when Ayoze Perez broke free from the opposition defence before getting a shot away at goal which was deflected narrowly wide.
Substitute Aguero made sure of the points in added time, however, finishing from close range after pouncing on a rebound ahead of Fabricio Coloccini. body check tags ::