Question

Shryia read a book cover to cover in a single session, at a constant rate. After reading for 1.5 hours, she had 402 out of the total 480 pages left to read. Let y represent the number of pages left to read after x hours.

Answer 1

Answer:

y = 480 - 268x.

Step-by-step explanation:

Shryia read a book at a constant rate.

She reads 402 pages in 1.5 hours.

So, the rate of reading is $\frac{402}{1.5} =268$ pages per hour.

If she read x hour then she will read 268x pages.

Now, there are a total 480 pages and the number of pages left to read is y = 480 - 268x.  

So, this is the equation that relates x and y. (Answer)

Answer 2

Answer:

$y=-52x+480$ .

Step-by-step explanation:

Shryia read a book cover to cover in a single session, at a constant rate.

Let y represent the number of pages left to read after x hours.

It is given that After reading for 1.5 hours, she had 402 out of the total 480 pages left to read.

It means the line passes through the points (0,480) and (1.5, 402).

If a line passes through two points, then the equation of line is

$y-y_1=\dfrac{y_2-y_1}{x_2-x_1}(x-x_1)$

$y-480=\dfrac{402-480}{1.5-0}(x-0)$

$y-480=\dfrac{-78}{1.5}(x)$

$y-480=-52x$

$y=-52x+480$

Therefore, the required eqaution is $y=-52x+480$.