$.\quad \dfrac{-5x}{8x+7}-\dfrac{6x^3}{3x+1}\\\\\\=\dfrac{-5x}{8x+7}+\dfrac{-6x^3}{3x+1}\\\\\\=\dfrac{-5x}{8x+7}\bigg(\dfrac{3x+1}{3x+1}\bigg)+\dfrac{-6x^3}{3x+1}\bigg(\dfrac{8x+7}{8x+7}\bigg)\\\\\\=\dfrac{-15x^2-5x}{(8x+7)(3x+1)}+\dfrac{-48x^4-42x^3}{(8x+7)(3x+1)}\\\\\\=\large\boxed{\dfrac{-48x^4-42x^3-15x^2-5x}{(8x+7)(3x+1)}}$

5 0

3 years ago

A distance travaled by train in three hours with a constant speed of r miles per hour

True [87]

The distance travelled by the train with constant speed of r miles will be 3r.

<h3><u>What is Speed?</u></h3>

The most crucial scientific notion is measurement. Base or physical fundamental units are used to quantify a wide range of quantifiable quantities.
One such measurable metric is speed, which calculates the ratio between the distance an object travels and the time needed to cover that distance. Let's explore speed in-depth in this session.
The pace at which an object's location changes in any direction. When an object travels the same distance in the same amount of time, it is said to be moving at a uniform speed.
When an object travels a different distance at regular intervals, it is said to have variable speed.

We know the formula of distance linking the speed and the time.

Distance = speed × time

Substituting the given values to get:

Distance = r × 3

Distance = 3r

Know more about Speed with the help of the given link:

brainly.com/question/6280317

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5 0

2 years ago