how do you calculate this on a calculator?

Pertend I never posted! 

The literal interpretation of this:    -790 +- √790^2 - 4 (-60)(-1000) / 2(-60)

is this:     \(-790\pm\sqrt{790}^2-\frac{4(-60)(-1000)}{2}(-60)\)

However, I think what you probably mean to say is this:    [  -790 ± √[ 790^2 - 4 (-60)(-1000) ]  ] / [ 2(-60) ]

which is:     \(\frac{-790\pm\sqrt{790^2-4(-60)(-1000)}}{2(-60)}\)

The only way that a calculator would know that  -790  is part of the numerator is if you put parenthesees around the entire numerator. The same goes for the denominator.

Now because of the  ±  , to enter this expression into a normal calculator we have to enter both expressions separately.

The first expression is:  (-790+sqrt(790^2-4(-60)(-1000)))/(2(-60))

The second expression is:     (-790-sqrt(790^2-4(-60)(-1000)))/(2(-60))

I took out the spaces, changed the brackets to parenthesees, and wrote  sqrt  instead of  √  so that you can select each expression and copy and paste it directly into the calculator on this website.

For the first one you should get approximately  1.419

For the second one you should get approximately  11.748

If you use a calculator like WolframAlpha you can input it like this, see here.

I don't know if that exactly answers your question....

If you just want to know how to get  240000, just enter:  4*60*1000