Question

Cynthia needs to get in shape and decides to start walking. On the first day she walked for 10 minutes, the second days for 15 minutes, the third day for 20 minutes, and fourth day for 25 minutes and so on. Show how to calculate the number of minutes she walked on day 20.

Answer 1

Answer:

Step-by-step explanation:

x = days, y = minutes

first day, she walked for 10 minutes......(1,10)

2nd day, she walked for 15 minutes.....(2,15)

now, we find the slope...

(1,10) , (2,15)

slope = (y2 - y1) / (x2 - x1) = (15 - 10) / (2 - 1) = 5/1 = 5

now we use y = mx + b.....we are looking for b, the y int

y = mx + b

slope(m) = 5

u can use either set of points...(1,10)...x = 1 and y = 10

now we sub and find b

10 = 5(1) + b

10 = 5 + b

10 - 5 = b

5 = b

so this equation is y = 5x + 5

so to calculate the number of minutes she walked on day 20, sub in 20 for x and solve for y

y = 5x + 5

y = 5(20) + 5

y = 100 + 5

y = 105 <=== she walked for 105 minutes