Question

Which of the following equations would not be a line when graphed? Explain how you can tell by just looking at the equations.

y = 3x+4
y= 2/x
y= -5x
y= 6x^2 -7

Answer 1

y=2/x. this equation has degree -1 whereas linear functions have degree 1

y=6x²-7 is nonlinear as it is degree 2

Answer 2

`y=(2)/(x)`

`y= 6x^(2) -7`

Explanation:

A linear function is one that has the following form:

`y= mx +b`

Where m corresponds to the slope (degree of inclination of the line), and b the cut point on the y-axis.

Now we search among the options those that correspond to the linear function formula

a.

`y= 3x+4`

Is a linear function where

`m=3\\ b=4`

b.

`y=(2)/(x)`

Is not a linear function equation since the variable x is in the denominator

c.

`y=-5x`

Is a linear function where

`m=-5\\ b=0`

d.

`y= 6x^(2) -7`

Is not a linear function since the variable x is squared.