Question

Two walls and the ceiling of a room meet at right angles at point p.A fly is in the air one metre from one wall and eight meters from another wall and 9 meters from point p.how many meters is the fly from the ceiling?

Answer 1

Answer:

distance form ceiling is 4

Step-by-step explanation:

Since we are given that

distance from one wall = x = 1

distance from from other wall = y = 8

distance from point p and origin = D

Let the distance from the ceiling is z then according to distance formula

in space for the point p(x , y , z) .

D = √(x² + y² + z²)

Putting the values we get

9 =√(1² + 8² + z²)

Taking square on both sides we get

     9² = (1² + 8² + z²)

 ⇒ 81 = 1 + 64 + z²

 ⇒ z² = 81 - 65 = 16

Taking under root on both sides we get

     z² = ±4

So there are two possibilities for z

Therefor the point is either (1 , 8 , 4) or (1 , 8 , -4)

Thus distance from ceiling in both cases is 4.