First, you have to find which two numbers go into 24 when multiplied.
24=
6×4
2×12
24×1
-6×4
-2×12
-24×1
Then you add each set of numbers together.
6+4=10
2+12=14
24+1=25
-6+4=-2
-2+12=10
-24+1=-23
6+(-4)=1
2+(-12)=-10
24+(-1)=23
Then you find which set when added makes 4. Since none of these are 4, it is no solution.
