square root of (-10) squared -4(1)(26)

This looks like the quadratic formula if I've ever seen one. :)

I'm thinking this is what you mean:

 

$$\sqrt{(-10)^2 -4(1)(26)$$

 

$$\sqrt{100-(4)(26)$$

 

$$\sqrt{100-104}$$

 

$$\sqrt{-4}$$

 

We can't take the square root of a negative number, it doesn't make any sence! What we do then is break this down into √-1 x √4, and we just express √-1 as i. "i" stands for imaginary number. We just call √-1 "imaginary."

 

$$\sqrt{-1}\times\sqrt{4}$$

 

$$i \times \sqrt{4}$$

 

The square root of 4 is 2:

 

$$i \times 2$$

 

Which we write as:

 

$$2i$$

 

There you go! you answer is 2i.