Sthe ordered pair (4, 12) a solution to the equation y = 3x?

if yes, is it the only solution?

a.
yes, and it is the only ordered pair that fits the equation.

b.
no, the ordered pair does not fit the equation.

c.
yes, but it is not the only solution to the equation.

To determine if the given coordinate of a point is a solution to the equation, substitute the abscissa to x and solve for the value of y. If the y obtained from the calculation equals to the ordinate of the point then, it is a solution. With the given above, substituting 4 to the given equation yields y = 12. The value of y is equal to that of the ordinate. Therefore, it is a solution.

The answer to this item is letter C because other ordered pair such as (-4, -12) may also fit the equation. 

X= 2 he can buy 2 packs of cards for $12 and an action figure for $3 so he would spend $15 in total plus the free poster