Dan started with 69 cards
Step-by-step explanation:
Let x be the initial number of cards
Then
According to "Dan bought 7 new baseball trading cards to add to his collection"

The next day his dog ate half of his collection.

There are now only 38 cards left.

Multiplying both sides by 2

Subtracting 7 from both sides

Hence,
Dan started with 69 cards
Keywords: Linear equation, word problems
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Answer:
0
Step-by-step explanation:
x+12 = 9+2x +3
x = 12-12
x = 0
If the area of the paper is 625 sq in, the length of one side of this square is sqrt(625 sq in), or 25 inches. That's the min. side length of an easel that is to support the whole sheet of paper along its lowest side.
The answer is -4 because 4+2 is equal to 6 and then 6-2 is equal to 4 and then times into the number of 2 the answer is 4x2 is equal to 8 and then minus into the negative 5 an the answer is -4.