Answer:
The speed of the plane in still air was 90 mph
The speed of the wind was 30 mph
Explanation:
Your first step would be to make two equations so you can cancel them out and find what each variable is. So, I divided 1560 by 13 and got 120 mph which represents the plane's speed plus the wind's speed. Next, to find the speed of the trip to go back, I divided 1560 by 26 which got me to 60. This represents the plane's speed minus the wind's speed to find the way back. Once, you have these equations, line them up and use either method of elimination or substitution. I used elimination because you could see the variable "w" cancelling out very easily. Solve the equation and substitute the new value of the variable to get the other value.
p+w=120
p-w=60
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2p=180
p=90
p+w=120--> 90+w=120--> w=30
W: 30 mph
P: 90 mph
I hope this helps!!