# How do you find the slope and intercept of y= -2/5x + 20?

May 17, 2018

$\text{slope "=-2/5," y-intercept } = 20$

#### Explanation:

$\text{the equation of a line in "color(blue)"slope-intercept form}$ is.

•color(white)(x)y=mx+b

$\text{where m is the slope and b the y-intercept}$

$y = - \frac{2}{5} x + 20 \text{ is in this form}$

$\text{with slope "=-2/5" and y-intercept } = 20$

May 17, 2018

Slope $= - \frac{2}{5}$

$y$-intercept $= 20$

#### Explanation:

The given equation is the standard slope-intercept form of a straight line equation,

$y = m x + c$

where

• $m =$ slope $\to$ tangent of the angle made by the straight line intercepting one of the axes ($x$ or $y$)
• $c =$ the $y$-intercept, which remains constant.

Thus putting your equation in accordance with the standard equation, the slope is $- \frac{2}{5}$ and the $y$-intercept is $20$.

graph{y = -2/5x + 20 [-80, 80, -40, 40]}

Since the slope is negative in magnitude, the tangent of the angle is greater than ${180}^{\circ}$ and hence, the straight line cuts the positive $x$ axis. Otherwise, in case of a positive slope, the straight line only cuts the positive $y$ axis, thus giving us the intercept.

Here the straight line cuts the positive $y$ axis at $\left(0 , 20\right)$ and hence the $y$-intercept is $20$.