What 2 numbers add up to 37 and multiply to - 210?

Let us assume the two unknown numbers to be "x" and "y".

Then

x + y = 37

And

xy = - 210

x = - 210/y

Now let us put the value of "x" in the first equation, we get

x + y = 37

- (210/y) + y = 37

y^2 - 210 = 37y

y^2 - 37y - 210 = 0

y^2 - 42y + 5y - 210 = 0

y (y - 42) + 5 (y - 42) = 0

(y - 42) (y + 5) = 0

So when

y - 42 = 0

y = 42

Then

x = - (210/42)

= - 5

Again when

y + 5 = 0

y = - 5

Then

x = 42

So the two unknown numbers are 42 and - 5. I hope the procedure is clear enough for you to understand.