Question

Which of the following has a graph that is a straight line?

Answer 1

$y = 2x + 7$ because it's a linear function.

Answer 2

Answer:

Equation 1: y = 2x + 7

Step-by-step explanation:

In general the equation of a straight line is:

y=mx+c where m is the slope of the line and c is the y intercept

Or we can say that a graph is a straight line if it is a linear function.

Equation 1: y = 2x + 7

It is a linear function hence, its graph is a straight line

Equation 2: y² = x − 1

 It is not a linear function hence, its graph is not a straight line

Equation 3: y = 2x² + 4

 It is not a linear function hence, its graph is not a straight line

Equation 4: y = 3x³

It is not a linear function hence, its graph is not a straight line

Hence, The equation whose graph is a straight line is:

Equation 1: y = 2x + 7