Dylan loves reading. He went to buy books from a bookstore. A school bag and 3 books cost $180. A school bag and 5 books cost $270

Question

Dylan loves reading. He went to buy books from a bookstore. A school bag and 3 books cost $180. A school bag and 5 books cost $270. How much did each book cost?

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Dulcie 4 weeks 2023-01-14T17:49:24+00:00 2 Answers 0 views 0

Answers ( 2 )

  1. thaiduong
    0
    2023-01-14T17:51:05+00:00
    Reply
    Answer:
    Each book costed 45$.
    Step-by-step explanation:
    Let x represent the price of a school bag and y represent the price of a book.
    we get the following system of equations:
    x+3y=180  (equation 1)
    x+5y=270 (equation 2)
    using equation 1: x=180-3y
    then we substitute x in equation 2 in order to find y:
    180-3y+5y=270
    180+2y=270
    2y=270-180=90
    y=90/2=45
    and we know that y represents the price of a book, so each book costs 45$.

  2. thuthao
    0
    2023-01-14T17:51:08+00:00
    Reply
    School bag _ y
    book _ x
    system:
    y+3x=180
    y+5x=270
    y=180-3x (and we put that instead of ‘y’ in the second equation)
    (180-3x)+5x=270
    180+2x=270
    2x=90
    x=45
    so one book costs $45
    and school bag:
    y+3×45=180
    y+135=180
    y=180-135
    y=45

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