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
Learn more about linear equations at:
#LearnwithBrainly
Answer:
The theater has 32 rows
Step-by-step explanation:
The rule of the sum of n terms of an arithmetic sequence is S =
(a + l), where
∵ The number of seats per row follows an arithmetic sequence
∵ The first row has 26 seats
∴ a = 26
∵ The last row has 150 seats
∴ l = 150
∵ The theater seats are 2,816
∴ S = 2,816
→ Substitute these values in the rule of the sum above to find n
∵ 2,816 = (26 + 150)
∴ 2,816 = (176)
∴ 2,816 = 88n
→ Divide both sides by 88
∴ 32 = n
∵ n represents the number of the rows
∴ The theater has 32 rows