# What is the slope and y-intercept of this line 2x+y=7?

Oct 3, 2016

slope = - 2
y-intercept = 7

#### Explanation:

The equation of a line in $\textcolor{b l u e}{\text{slope-intercept form}}$ is

$\textcolor{red}{\overline{\underline{| \textcolor{w h i t e}{\frac{a}{a}} \textcolor{b l a c k}{y = m x + b} \textcolor{w h i t e}{\frac{a}{a}} |}}}$
where m represents the slope and b, the y-intercept.

The advantage to having the equation in this form is that m and b may be extracted ' easily'.

$2 x + y = 7 \text{ can be expressed in this form}$

subtract 2x from both sides.

$\cancel{2 x} \cancel{- 2 x} + y = 7 - 2 x$

$\Rightarrow y = - 2 x + 7 \text{ is now in slope-intercept form}$

Thus $\text{slope" =-2" and y-intercept} = 7$
graph{-2x+7 [-14.24, 14.24, -7.12, 7.12]}