What two numbers multiplies to - 225 but adds to 16

first you do - 225+16 which equals - 209

then you dived it by 2 which is not a whole number

then you go to 3 - no

4 - no

5 - no

6-no

7-no

8-no

9-no

10 - no

11 - yes

so theequation is

11 * (-19) + 16 = - 225

Give the 2 numbers variables, say x and y.

then they multiply to - 225. this means xy=-225

they add to 16. this means x+y=16

y=16-x

substitute y=16-x onto xy=-225 to get x (16-x) = - 225

then expand to get 16x-x^2=-225

rearrange to get a quadratic: x^2-16x-225=0

x = (16 + (16^2-4*-225) ^0.5)) / 2 or

x = (16 - (16^2-4*-225) ^0.5)) / 2