Question

Which answer is the slope of of the line with equation 5x+y=15

Answer 1

This line is given to us in standard form, $Ax+By=C$, but it's easiest to see the slope when we convert to slope-intercept form $y=mx+b$, where m is the slope.

We are going to solve for y.

$5x+y=15\\5x-5x+y=-5x+15\\y=-5x+15\\m=-5$

The slope is the coefficient of the x-term, –5.