The equation y = ax describes the graph of a line. if the value of a is positive, the line:

a. goes up and to the right.
b. is horizontal.
c. is vertical.
d. goes down and to the right.

If the value a is positive in the linear equation y = a x ( for example: y = 2 x ) then the line ( from the left to the right ) must go up and to the right. It also passes through the origin ( 0, 0 ).           For x = 1: y = 2 * 1 = 2, so that point is ( 1, 2 ),  x2 > x1,  and y2 > y1.A. goes up and to the right.
 

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