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answer is given. -5 volts, but how?

 

As far as this problem goes. i'm just starting out, and with the numbers given to me i'm sure i have to apply the resistors numbers with the 1 Volt given to me. I'm just not sure how i'm supposed to get -5 volts.

 

Use the equation for the gain of an inverting op amp. It surely must be in your textbook.

 

Have a look here.

 

So it is inverted. and the 50K resister is giving me the -5. ok that makes much more sense now. wondering how it gave it -5.

 

You need to understand how to analyze the circuit and not just how to look up a formula to throw at it. For this circuit, the analysis would proceed as follows:

Q1) Assuming the opamp is operating in its active region, what is the voltage at the inverting input to the amplifier?

Q2) What is the current (magnitude and direction) of the current in the input resistor given an input voltage Vin and the answer to Q1?

Q3) What is the current (magnitude and direction) of the current in the feedback resistor?

Q4) What is the voltage at the output given the answers to Q1 and Q3?