State if three numbers can be the measure of a triangle. 12, 12, 20
10,3,7
7,7,11
24, 9, 12

Let the 3 sides of a triangle be a,b and c
For it to be a triangle then
a + b > c , a + c > b , b + c > a

12 , 12 , 20
12 + 12 > 20
24 > 20

12 + 20 > 12
32 > 12
Hence is a triangle

10,3,7
3 + 7 10
10 = 10
Hence is not a triangle since it does not satisfy the rules above

7,7,11
7 + 7 11
14 > 11

11 + 7 7
18 > 7
Hence the figure formed is a triangle

24,9,12
9 + 12 24
21 < 24
Hence is not a triangle

The rule is that for 3 numbers to form the sides of a triangle then the sum of any 2 of the numbers should be equal to the third