Question 70078
Determine if the ordered pair is a solution of the equation 
3x-y=12 
Substitute the x and the y values into the equation to see if you get a true statement:

(0,4): 3*0-4=12; -4=12; not true so pt is not a solution.

(4,0): 3*4-0=12; 12=12; true so pt is a solution

(-1,15): 3*-1-15=12; -3-15=12;-18=12; falso so pt is not a solution

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Cheers,
Stan H.