Answer:
x=9, y=15. (9, 15).
Step-by-step explanation:
y=2x-3
y=x+6
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2x-3=x+6
2x-x-3=6
x-3=6
x=6+3
x=9
y=9+6=15
Answer:
0.0000625
Step-by-step explanation:
Answer:
x=0
y=3
Step-by-step explanation:
2(x+3)=2x+6, substituting the first equation in the second
2x+6=2x+6, rearranging the equations
2x-2x=6-6
0=0
y=0+3
y=3
Answer:
System of equations:
20x + 30y = 650
x + y = 25
Time underwater = 10 hours
Time at the surface = 15 hours
Step-by-step explanation:
Let x = time underwater at 20 km/h.
Let y = time on the surface at 30 km/h.
speed = distance/time
distance = speed * time
distance underwater: 20x
distance on the surface: 30y
total distance: 650
20x + 30y = 650
total time: x + y
total time: 25
x + y = 25
20x + 30y = 650
x + y = 25
20x + 30y = 650
-20x - 20y = -500
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10y = 150
y = 15
x + y = 25
x + 15 = 25
x = 10
