How do you know if a data is linear or quadratic?

Linear data goes along a line and progresses in a linear or straight fashion 
e.g) y=x+5 

Quadratic data goes in an exponential fashion and progresses much more rapidly
e.g) y=x^2+x+6

If it is linear it could cross the x axis 

Answercounterclockwise rotation about the origin by 180 degrees followed by reflection about the y-axisexplanationthe given figure has verticesrecall that for counterclockwise rotation about the origin, when we rotate figure pqrs counterclockwise through an angle of 180° about the origin, the coordinates will becomenext, we reflect in the y-axis by negating the x-coordinates of the resulting figure to obtain,therefore the correct answer is c