Basic mathmatical concepts( multiplication)

Question

Here is a conundrum I pondered upon while solving an equation - 2x2 , generally means we are adding 2 two times , that is , 2+2 Then , (-2)x(-2) , should go like this (-2)+(-2)=-4 , But , that's not true , the answer is +4 . Can anybody figure out and help me with it..

Answer 1

We need to refer to axioms and since $+1$ is the neutral element for product, the idea is that we have

• $(-2) \cdot (+1)=-2$

and then

• $(-2) \cdot (-1)=+2 \implies (-2) \cdot (-2)=+4$

For a detailed discussion refer to the related

• Why is negative times negative = positive?