The altitude of a plane as it begins to descend is shown by the linear equation
a = 28,500 – 1800m, where a is the plane’s altitude, in feet, and m is minutes.

What is the plane’s altitude when m = 9?

Question

The altitude of a plane as it begins to descend is shown by the linear equation 
a = 28,500 – 1800m, where a is the plane’s altitude, in feet, and m is minutes.
 
What is the plane’s altitude when m = 9?

anonymous · Answer

Would it be 0 because altitude can't be negative for a plane?

anonymous · Answer

I set it up wrong it would be 12,300

anonymous · Answer

Could you tell me how you got that?

anonymous · Answer

of course. plug in 9 for 1800(m) and you get 16,200. Subtract that from the initial 28,500 and you get 12,300

anonymous · Answer

Thank you so much!

anonymous · Answer

It's no problem. anything else i can help you with?

anonymous · Answer

No, that's it. :)

anonymous · Answer

ok. good luck!