Answer:
1. Non - linear
2. Linear
3. Linear
4. Linear
Step-by-step explanation:
All linear equations can be expressed in the form of
[tex]y=mx+b[/tex]
where m is slope and b is y-intercept.
Horizontal line is a special case of linear functions, where slope is 0. It means y=b is also a linear funcion.
First function is
[tex]72=x^3+y\Rightarrow y=-x^3+72\neq mx+b[/tex]
It is a non linear function.
Second function is
[tex]y+1=5(x-9)\Rightarrow y=5x-45-1\Rightarrow y=5x-46=mx+b[/tex]
It is a linear function.
Third function is
[tex]7y+2x=12\Rightarrow y=\dfrac{12-2x}{7}=-\dfrac{2}{7}x+\dfrac{12}{7}=mx+b[/tex]
It is a linear function.
Fourth function is
[tex]4y=24\Rightarrow y=6=0x+6=mx+b[/tex]
It is a linear function.
