Question

JOe goes to the gym to run and swim. When running he burns 35

Answer 1

Answer:the length of time he spent running is 8 minutes.

the length of time he spent swimming is 15 minutes.

Step-by-step explanation:

Let x represent the length of time he spent running.

Let y represent the length of time he spent swimming.

He exercised for a total of 23 minutes. This means that

x + y = 23

When running he burns 35 calories per minute, and when he swims he burns 30 calories per minute. He has burned 730 calories after exercising. It means that

35x + 30y = 730 - - - - - - - - - -1

Substituting x = 23 - y into equation 1, it becomes

35(23 - y) + 30y = 730

805 - 35y + 30y = 730

- 35y + 30y = 730 - 805

- 5y = - 75

y = - 75/ -5

y = 15

Substituting y = 15 into x = 23 - y, it becomes

x = 23 - 15 = 8