The requirement engineering is one of the emerging sections in software engineering. The main factors that a requirement engineering process considers are business requirements and user requirements and provide solutions according to it. We have proposed a requirement engineering model based on the Tropos goal model. A modified Tropos goal model is used in the proposed goal risk model. The goal risk model consists of three layers, and in the top level goals to be achieved by the process is plotted and in the second level, the events that triggers the goals and in the bottom level, the supporting parameters for the goal and events are plotted. The risk analysis of the proposed GR model is conducted based on one analyses i.e. the cost to risk analysis. The experimental evaluation is carried out on a case study considering a software development company. The risk affinitive value is calculated from the different set of risk parameters, which is set like high, medium and low. The risk parameters clearly evaluate the affinity of that event to a particular set of goals. This parameter reduces the limitation in the previous work, like occurrence of same cost to risk values. According to the proposed approach distinct cost to risk values are achieved. Finally, the candidate solutions with low cost are selected