The speed of a boat in still water is x km/hr and speed of the stream is 3 km/hr (i) Write the speed of the upstream, in terms of x (ii) Write the speed of the downstream, in terms of x (iii) If the boat goes 15 km upstream and 22 km downstream in 5 hours, write an equation in x to represent the equation in x to represent the statement (iv) Solve the equation to evaluate x
whoever solves it step by step will get brainliest answer
Step-by-step explanation:
Living things move, respond to stimuli, reproduce and grow, respire, and are dependent on their environment. Most living things need food, water, light, temperatures within defined limits, and oxygen. … Some non-living things, such as rocks and water, were never living
Answer:
Let x be the speed of the stream.
⇒ Speed of the boat in still water is 8kmhr
⇒ The speed of the boat in upstream is 8−xkm/hr
⇒ The speed of the boat in downstream is 8+xkm/hr
⇒ The time taken by the boat to cover 15km= 8−x
15 hr
⇒ The time taken by the boat to cover 22km= 8+x22 hr
According to the question,
⇒ 8−x
15 + 8+x 22
=5
⇒ 15(8+x)+22(8−x)=5(8−x)(8+x)
⇒ 120+15x+176−22x=5(64−x 2 )
⇒ 296−7x=320−5x 2
⇒ 5x 2 −7x−24=0
⇒ 5x 2
−15x+8x−24=0
⇒ 5x(x−3)+8(x−3)=0
⇒ (x−3)(5x+8)=0
⇒ x−3=0 and 5x+8=0
=3 and x=− 5
8
Speed cannot be negative.
∴ The speed of the stream is 3km/hr