# What is the slope of y=-x?

Aug 2, 2018

The slope is -1.

#### Explanation:

This is in slope-intercept form, or $y = m x + b$, where $m$ is the slope and $b$ is the $y$-intercept.

Since we know the slope is the value multiplied by $x$, the slope is $- 1.$

Hope this helps!

Aug 2, 2018

$- 1$

#### Explanation:

$\textcolor{b l u e}{\text{The concept of slope}}$

Slope (gradient) is the amount of up or down on the y-axis for a given amount of along on the x-axis.

Suppose for example the slope is 2.

Another way of writing 2 (which is not done very often) is $\frac{2}{1}$

As slope $\to \left(\text{amount of up or down")/("amount of along}\right)$ then we have the amount of 2 as the up or down and we have the value of 1 for along.

As the 2 is positive ,by convention, it is UP.

A negative value for the up or down by convention is DOWN.
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$\textcolor{b l u e}{\text{Answering the question}}$

Given: $y = - x$

Write this as: $y = - 1 x \leftarrow \text{ bad practice!}$

This is the same as $\frac{- 1}{1}$

So for 1 along the line goes DOWN 1

Thus the slope is $- 1$

Aug 2, 2018

$- 1$

#### Explanation:

Recall slope-intercept form

$y = m x + b$, with slope $m$ and a $y$-intercept of $b$. With this in mind, we can rewrite our equation as

$y = - x + 0$

We see that our slope, or coefficient on $x$, is $- 1$.

Hope this helps!