Give a seven-year-old 12 − 9 = 3 and ask what 12 − 3 makes, and you can almost hear them start counting backward. Yet the answer is already sitting in the first fact. This 2nd grade fact triangle subtraction worksheet helps your child see it. At the top, a fact triangle holds 12, 9 and 3, with its two subtraction facts written beside it. A short rule explains the trick: swap the numbers after the minus sign and the equal sign. Then eight sets follow, from small ones like 6, 1 and 5 to bigger ones like 37, 10 and 27. For each set, your child writes a first and a second related fact. A second page gives the answer key.