Is y + 4 = 2x linear ?

1 Answer
Feb 27, 2018

Yes, it is a linear equation.

Explanation:

Given:

#y+4=2x# is in the point-slope form for a linear equation:

#y-y_1=m(x-x_1)#,

where:

#m=2# (the slope), and the point #(x_1,y_1)# is #(0,-4)#.

The equation can be converted to slope-intercept form #(y=mx+b)# by solving for #y#.

#y+4=2x#

Subtract #4# from both sides.

#y=2x-4# is in slope-intercept form:

#y=mx+b#,

where:

#m# is the slope (#2#), and #b# is the y-intercept (value of #y# when #x=0#.

We can also convert #y+4=2x# to the standard from :

#Ax + Bx=C#,

where #A and B# are coefficients, and #C# is the constant (has no coefficient).

#y+4=2x#

Subtract #4# from both sides.

#y=2x-4#

Subtract #2x# from both sides.

#y-2x=-4#

All of these linear equations will give the same graph.

graph{y=2x-4 [-10, 10, -5, 5]}