Question

An airplane 30,100 feet above the ground begins descending at the rate of 2,150 feet per minute. Write and solve a linear equation to find how long it will take the plane to reach the ground.

Answer 1

Answer: 14 minutes

Step-by-step explanation:

Given : An airplane 30,100 feet above the ground begins descending at the rate of 2,150 feet per minute.

i.e. Initial position of airplane = 30,100 feet above the ground

Speed = -2,150 feet per minute.

let x denotes the number of minutes .

Then the distance traveled by airplane in x minutes = Speed × Time

= -2150x

So the required linear equation :-

$f(x)=30100-2150x$ , where f(x) is the distance from graound after x minutes.

When plane reaches the ground then f(x)=0.

$\Rightarrow0=30100-2150x\\\\\Rightarrow\ 2150x=30100\\\\\Rightarrow\ x=\dfrac{30100}{2150}=14$

Hence, it will take 14 minutes to reach the ground.

Answer 2

30,100= 2,150x
Total            x=number per minute
divide 2,150 0n both sides 
30,100= 2,150x
              ____
              2,150
Cross it out. Your only left with x.
Then divide 30,100 by 2,150 = 14
x= 14 minutes it will take to completely descend
Your welcome.