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## Addition & Subtraction Triangular Flash Cards The numbers on the cards are upright, meaning that if the card is turned 180 degrees, then the numbers will be upside down. You are supposed to hold the cards right side up, pointy-side down. I made this set like this on purpose, but I do not remember why. I have two other sets of triangular flash cards and you can find them via the links above or here: Blue Triangular Math Facts Cards & Black Triangular Math Facts Cards

To use the cards, cover one of the numbers with your thumb, show the card to your child and he should try to figure out what the covered number is based on the other two numbers.

The math sentences behind this are:
Subtracting: x plus a known number = a known number [ x + 5 = 9 ]
Subtracting: a known number plus x = a known number [ 4 + x = 9 ]
Adding: a known number plus a known number = x [ 4 + 5 = x ]

Adding: Cover the bottom number
Subtracting: Cover one of the top numbers

A blank printable of the cards is also available and linked near the bottom of this page.

### The Printable Files

54 Cards
To get all the facts you must print all the cards. There are no zeros in this set. If you need zeros, use a different set [linked above].
Recommend: Print on card stock. Blank Cards

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