Question 104909
A) y=4x-1 
B) y=3x+15 
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Since these graphs are linear we only need 2 points (x,y) for each line. I like to use the x and y intercepts, if fractions don't get involved, because there are less numbers to deal with, so I make less mistakes.
Keep the x and y as small as possible so the points fit on the graph.
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y=4x-1
x=0, y= -1 (0,-1)
x=1, y= 4-1=3 (1,3)
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y=3x+15
x= -5 y= -15+15=0 (-5,0)
x= -3 y= -9+15=6 (-3,6)
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put the points on your graph paper and draw the lines and it should look like this.

{{{graph(500,500,-2,18,-10,75,4x-1,3x+15)}}}
The lines do cross do cross when x=16  when y=63 !!! That is the correct answer.
Check:
63=4*16-1 true
63=3*16+15 true
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Ed