A motor boat whose speed in still water is 18 km/h takes 1 hour more to go 24 km upstream than to return downstream. Taking the stream speed as x km/h, the equation reduces to x^2 + 48x - 324 = 0. Find the stream speed (km/h) using the quadratic formula.

Question

Accepted Answer

6. 24/18 - x - 24/18 + x = 1 => 24[(18+x) - (18-x)] = (18-x)(18+x) => 24(2x) = 324 - x^2 => x^2 + 48x - 324 = 0. D = 48^2 + 4(324) = 2304 + 1296 = 3600, √D = 60. x = -48 + 60/2 = 6. Stream speed = 6 km/h.

A motor boat whose speed in still water is 18 km/h takes 1 hour more
to go 24 km upstream than to return downstream. Taking the stream
speed as $x$ km/h, the equation reduces to $x^{2} + 48 x - 324 = 0$ .
Find the stream speed (km/h) using the quadratic formula.

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 The Quadratic Formula practice

A motor boat whose speed in still water is 18 km/h takes 1 hour moreto go 24 km upstream than to return downstream. Taking the streamspeed as x km/h, the equation reduces to x2+48x−324=0.Find the stream speed (km/h) using the quadratic formula.

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 The Quadratic Formula practice

A motor boat whose speed in still water is 18 km/h takes 1 hour more
to go 24 km upstream than to return downstream. Taking the stream
speed as $x$ km/h, the equation reduces to $x^{2} + 48 x - 324 = 0$ .
Find the stream speed (km/h) using the quadratic formula.