2 days late, but the answer is no solution. solving a system of equations means finding where they intersect, but by looking at these equations, you know that they never intersect--they're parallel.
they share a slope (2), making them either parallel or "the same line", but the different x-intercepts (9 and -9) mean that they're different lines. they have no solution, or no intersection point, because they're parallel lines.
Answer:
total is 47.70
Step-by-step explanation:
change is $12.30
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
--------------------------------
10y = 150
y = 15
x + y = 25
x + 15 = 25
x = 10
202 + 8 = 210
210 + 8 = 218
218 + 8 = 226
The number is 226.
