Consider the cascade of systems shown below Suppose both subsystems are linear. Is the overall system linear? Show your reasoning, Suppose both systems are time-invariant. Is the overall system time-invariant? Solution Linear systems means those systems who obey the principles of homogeneous and Superposition are said to be linear. Since given two systems are linear the over responses will be also linear. Time invariant systems means whose response remains constant even the time changes. Hence given cascaded response will be also Have Time invariant response..