X-y=2 (*-2) --> -2x+2y=-4
2x+3y=14
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2x+3y=14
-2x+2y=-4
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5y=10
y=2
18 is the answer //////////////////
5z+7=32
5z+7-7=32-7
5z/5=25/5
z=5
4 hours and 15 minutes =4+15/60=4.25 hours
the average speed of the train = 250/4.25=58.82mph