Questions: Writing an equation of a line given its slope and y-intercept Write an equation in slope-intercept form for the line with y-intercept -9 and slope 2/5.

Writing an equation of a line given its slope and y-intercept

Write an equation in slope-intercept form for the line with y-intercept -9 and slope 2/5.

Transcript text: Writing an equation of a line given its slope and $y$-intercept Write an equation in slope-intercept form for the line with $y$-intercept -9 and slope $\frac{2}{5}$.

Solution

Solution Steps

To write the equation of a line in slope-intercept form, we use the formula $ y = mx + b $, where $ m $ is the slope and $ b $ is the y-intercept. Given the slope $ \frac{2}{5} $ and y-intercept $-9$, we can directly substitute these values into the formula to get the equation of the line.

Step 1: Identify the Slope and Y-Intercept

The slope $ m $ of the line is given as $ \frac{2}{5} $, which can be expressed as $ 0.4 $. The y-intercept $ b $ is given as $ -9 $.

Step 2: Write the Equation in Slope-Intercept Form

Using the slope-intercept form of a line, which is given by the equation: \[ y = mx + b \] we substitute the values of $ m $ and $ b $: \[ y = 0.4x - 9 \]