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2 years ago

Jackie runs and dances for a total of 55 minutes every day. She dances for 25 minutes longer than she runs.

Mathematics

1 answer:

AlladinOne [14]2 years ago

5 0

9514 1404 393

Answer:

A: x + y = 55; y - x = 25

B: 15 minutes running

C: no

Step-by-step explanation:

The two equations relate to the total number of minutes, and to the difference specified in the problem statement.

x + y = 55 . . . . . . total time is 55 minutes

y = x + 25 . . . . . . dances 25 minutes longer

We can substitute for y in the first equation to find the value of x, the time spent running.

x + (x +25) = 55

2x = 30 . . . . subtract 25

x = 15 . . . . . . divide by 2

Jackie spends 15 minutes running each day.

The value of y from is found using the second equation:

y = x +25 = 15 +25 = 40

Jackie <u>will not spend 45 minutes dancing</u> if she meets the requirements on times.

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