How do you create an inverting summing amplifier on a breadboard? I have all of my connections to the om amp correct. I am unsure of where I connect my 2 power sources, my + input source, and my two - input sources with two batteries. I have tried numerous combinations and nothing has worked please help

 

Can you post your schematic

 

here you go ... The resitors are in series to give an Req o 40k Ohms on top and 25k Ohms on the bottom

the gray wire in the bottom right corner is my V out

 

Hello,

What you have posted is a wiring diagram.
A schematic was asked for.
Can you post the schematicof the circuit?

Have a look at this page of the eBook for some ideas:
Averager and summer circuits

Bertus

 

Here is an example. Remember GND, +9 volt and -9 volt. Should be connected to your breadboard

 

I calculated Vout to be -2.85V ... But I am having difficulty assembling this one my breadboard. I have 9V sources for the power but I do not want to waste the battery which is why they were not in the picture

sorry here is actual drawing

I have the power connected like that and I am assuming that the positive input also connects to the ground ... but what about the sources ?

 

Hello,

The - side of the sources should go to ground, when the source is positive.

Bertus

 

so you are saying to connect everything to ground when the sources are generating a positive current? But doesn't this short circuit the system cause I am getting a value of zero when i do that

 

You did not post a schematic, instead you posted a fuzzy photo of a breadboard circuit.
We do not know if you are using an opamp since it does not have a part number, it might be an LM386 power amplifier IC and its pin numbers are different to the pin numbers of an opamp.

I am attaching a real schematic of an audio mixer circuit. It can drive a load not less than 22k ohms (the 330nF output capacitor C3 has a cutoff frequency of 22Hz with a load of 22k).

 

I see that you are summing DC voltages, not audio. Your answer is correct.
Here is the schematic of your circuit (but it is missing the power supply):

 

It seems to be working when I measure. I connected all the terminals to the negative. The only issue I have is that my measured values or off by a tens place. Everything else is correct my sign and the numbers ...

Nevermind made a dumb mistake was using wrong resistor value

 

I connected all the terminals to the negative.

What are "the terminals"? The inputs?
What is "the negative"? The negative 9V supply?

The only issue I have is that my measured values or off by a tens place.

What is "or off"? Do you mean are off?

 

made a silly mistake in circuit diagram measured values are equal to calculated values now

 

I calculated Vout to be -2.85V ... But I am having difficulty assembling this one my breadboard. I have 9V sources for the power but I do not want to waste the battery which is why they were not in the picture

sorry here is actual drawing

I have the power connected like that and I am assuming that the positive input also connects to the ground ... but what about the sources ?

It is common practice with opamps to identify inverting and non inverting inputs. No matter what you asume.