Answer:
(x, y) = (-6, 3)
Step-by-step explanation:
Maybe you want to solve ...
Use the first equation to substitute for y in the second:
2x +3(-2x -9) = -3
2x -6x -27 = -3
-4x = 24 . . . . . . . . . add 27, simplify
x = -6 . . . . . . . . . . . divide by -4
y = -2(-6) -9 = 12 -9 = 3
The solution is (x, y) = (-6, 3).
Answer:
A. a testable scientific question
The rate of change is 6 secs/foot in terms of seconds per foot.
1. 5 x 5
2. 7 x 28
3. 90 divided by 70
4. 40 divided by 5.
Hope this helps. #I'm11
Answer:
Wind speed = 30 mph
Plane speed = 270 mph
Step-by-step explanation:
Given that :
Distance = 600 miles
Let speed of airplane = a ; speed of wind = b
Net speed ; with wind = a + b
Net speed against wind = a - b
Time taken with wind = 2 hours
Time taken against wind = 2.5 hours
Recall :
Speed = distance / time ; distance = speed * time
(a + b) * 2 = (a - b) * 2.5
2a + 2b = 600
a + b = 300 - - - (1)
a = 300 - b
2.5a - 2.5b = 600
a - b = 240 - - - (2)
300 - b - b = 240
300 - 2b = 240
-2b = - 60
b = 30
a = 300 - 30
a = 270
Wind speed = 30 mph
Plane speed = 270 mph
