Question

Yesterday, Carmen went on a bike ride. Her average speed was 8

Answer 1

Answer:

Step-by-step explanation:

Yesterday, her rate was 8mph, her time was x hours.

Today, her rate was 13mph, her time was 13 - x hours.

So the total distance she biked on the two days is

d = 8x + 13(13 - x), or 169 - 5x

Answer 2

Answer:

$8x+13(9-x)$ or $-5x+117$ miles.

Step-by-step explanation:

Let x represent number of hours Carmen biked yesterday.

$\text{Distance}=\text{Speed}\times \text{Time}$

We have been given that yesterday Carmen's average speed was 8

miles per hour. So distance covered in x hours would be $8x$.

We are also told that Carmen biked for a combined total time of 9

hours. So the number of hours biked second day would be $9-x$. The distance covered in $9-x$ at a speed of 13  miles per hour would be $13(9-x)$.

Total distance covered by Carmen would be: $8x+13(9-x)$

$8x+117-13x$

$8x-13x+117$

$-5x+117$

Therefore, the total distance covered by Carmen in the two days would be $-5x+117$ miles.