# How do you graph y=-4-4x using the intercepts?

Mar 14, 2017

See explanation graph{-4-4x [-10, 10, -5, 5]}

#### Explanation:

To find the $x$ intercept, we must set $y = 0$ and solve for $x$

$0 = - 4 - 4 x \to 4 = - 4 x \to - 1 = x$

We found that $x = - 1$ so our $x$-intercept is at $\left(- 1 , 0\right)$
Note: The $x$-intercept is where our function crosses the $x$-axis

To find the $y$-intercept, we must set $x = 0$ and solve for $y$

$y = - 4 - 4 \left(0\right) \to y = - 4$

We found that $y = - 4$ so our $x$-intercept is at $\left(0 , - 4\right)$

Note: The $y$-intercept is where our function crosses the $y$-axis. Also, we didn't have to find the $y$-intercept this way because In any linear function the $y$-intercept is always the constant (or $\textcolor{red}{b}$) in the equation $y = m x + \textcolor{red}{b}$

Now that we have both s our $x$ & $y$ intercepts we can graph this (see graph).

Note that our slope is $- 4$ since the slope is the coefficient (or $\textcolor{b l u e}{m}$) in the equation $y = \textcolor{b l u e}{m} x + b$

I hope this was helpful and that you understand the topic a little better now!