X - 2y = - 9
7x + 2y = 1
x - 2y = - 9
(+)
7x + 2y = 1
___________
8x = - 8
x = - 1
- 1 - 2y = - 9
2y = 8
y = 4
i am a mathematics teacher. if anything to ask please pm me
Use the Pyth. Theorem to calculate the total distance flown by the plane in 3 1/2 hours:
d = sqrt(750^2 + 750^2) = 750sqrt(2) miles
Now divide this distance by the total time (3 1/2 hours):
750sqrt(2) miles
---------------------- = 303 miles per hour average
3.5 hours
Answer:
b
Step-by-step explanation: