0&4, 1&3, 2&2
To find two numbers that add up to 4 and multiply to -21, we can set up a system of equations. Let's call the two numbers x and y. We have the equations x + y = 4 and x * y = -21. By solving these equations simultaneously, we can find that the two numbers are 7 and -3. This is because 7 + (-3) = 4 and 7 * (-3) = -21.
-4
-49 and -4
79
169
5 and -4
-56
-1
8
20
The two square numbers which add up to 13 are 9 (which is equal to 3 squared), and 4 (which is equal to 2 squared).
-144
3 and 4
49 and 4
4 and 9.
5 and 4
9