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What is the speed of the wind? (Remember, y =speed of the wind.)Here's our system of equations:2(x + y) = 6003(x - y) = 600Enter the correct answer.0000DONEWe know that x = 250.Now let's solve for y.Clear allDOO?ProblemAt full speed, Hal travels 600 miles in 2 hourswith the wind. The same distance againstthe wind takes 3 hours.What's the maximum speed of Hal's airplanein still air? What's the speed of the wind?x = speed of the airplane in still airy = speed of the wind

User Mattbloke
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This is a case of simultaneous equations. We expand the equations

2(x + y) = 600 | eqn 1

3(x - y) = 600 | eqn 2

Expanding,

2x + 2y = 600 | eqn 3

3x - 3y = 600 | eqn 4

We employ the elimination method. That way we multiply eqn3 by 3 and eqn 4 by 2

Hence, we get

6x + 6y = 1800 | eqn 4

6x - 6y = 1200 | eqn 6

Next, we add eqns 4 and 6, we get

12x = 3000 | dividing both sides by 12

x=3000/12 = 250

We then substitute this value of x into eqn 1 to get

2(250) + 2y = 600

500 + 2y = 600 | minus 500 from both sides to get

2y = 600 - 500

2y = 100 | Dividing both sides by 2, we get

y = 100/2 = 50

Therefore, x = 250, y = 50

User Yu Wei Liu
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