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Suppose you have a point that is on both lines and its first coordinate is x. Since it is on the first line its second coordinate y can be found using the expression y = 2x + 4. Since it is on the second equation its second coordinate y can also be found using the expression is 2x + 16. Thus
Solve for x. Penny
Remember that the line y=2x+4 is the set of points (x,y) Thus the intersection is the point (x,y) where both equations hold. At that point it is valid to substitute (2x+4) for y Good Hunting!  


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