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horizontal equalities equations with numbers between 1 and 20
Assistance needed; this is definitely not 1st grade!
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To find horizontal equalities equations with numbers between 1 and 20, we can systematically go through each number, starting with 1 and ending with 20, and look for pairs of numbers that add up to the same sum.
Let's go through the numbers between 1 and 20:
1 + 1 = 2 (not equal)
1 + 2 = 3 (not equal)
1 + 3 = 4 (not equal)
...
1 + 19 = 20 (not equal)
2 + 1 = 3 (not equal)
2 + 2 = 4 (equal)
2 + 3 = 5 (not equal)
...
2 + 18 = 20 (not equal)
2 + 19 = 21 (not equal)
3 + 1 = 4 (not equal)
3 + 2 = 5 (not equal)
3 + 3 = 6 (equal)
...
3 + 17 = 20 (not equal)
3 + 18 = 21 (not equal)
3 + 19 = 22 (not equal)
Continuing this pattern, we can continue through each pair until we reach 20. Let's skip ahead to see if there are any more equalities.
18 + 1 = 19 (not equal)
18 + 2 = 20 (not equal)
18 + 3 = 21 (not equal)
...
18 + 18 = 36 (not equal)
18 + 19 = 37 (not equal)
19 + 1 = 20 (not equal)
19 + 2 = 21 (not equal)
...
19 + 18 = 37 (not equal)
19 + 19 = 38 (not equal)
So, through this systematic process, we have found that the only horizontal equalities equation with numbers between 1 and 20 is:
2 + 2 = 4