How to find the slope and y-intercept for y-2x<6?

2 Answers
Nov 20, 2017

y<2x+6

The slope is 2 and the y-intercept is 6.

Explanation:

y-2x<6

Solve for y to get the inequality into slope-intercept form:

y=mx+b,

where:

m is the slope, and b is the y-intercept.

Solve for y.

y-2x<6

Add 2x to both sides.

y<2x+6

The slope is 2 and the y-intercept is 6.

Nov 20, 2017

y-intercept: (0, 6)
Slope: m=2
The solution for y is given by the graph below.

Explanation:

The easiest way to evaluate this inequality is to pretend (for a moment) that we are actually dealing with the equation,

y-2x = 6

The y intercept of an equation occurs when x=0.

y-2x = 6

y-2(0) = 6

y = 6

So the y-intercept is the point (0, 6). The x-intercept occurs when y=0.

y - 2x = 6

0 - 2x = 6

-2x = 6

x = -3

So the x-intercept is the point (-3, 0). Draw a dashed line through these points to account for the inequality symbol.

The slope is the rise over the run.

m="rise"/"run"=6/3=2

![Desmos.com and MS Paint](useruploads.socratic.org)

The final step is to determine where to shade by choosing an easy point, like (0, 0). If plugging in this point makes the original inequality a true statement, then shade that entire side of the line.

y-2x<6

0-2(0)<6

0 < 6 is true.

So shade the side with the point (0, 0)

![Desmos.com and MS Paint](useruploads.socratic.org)