Systems of Equations: Word Problem

In summary, the problem asks for the speed of a plane and the speed of the wind given two different flight times. By setting up two equations using the variables x for the plane's speed and y for the wind's speed, we can solve for both values. The equations are 10x-10y=2880 and 5x+5y=1920. Solving for x and y, we get the values of 336 and 48, respectively.
  • #1
S.R
81
0

Homework Statement


A small plane flying into the wind takes 3 h 20 min to complete a flight of 960km. Flying with the wind, the same plane takes 2 h 30 mins to make the trip. What is the speed of the plane? What is the speed of the wind?


Homework Equations


N/A

The Attempt at a Solution


I'm unsure on how to set-up the two equations:

Let x represent the speed of the plane and y represent the speed of the wind.

7/3(x-y)=960

5/2(x+y)=960

Is this representation correct?
 
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  • #2
S.R said:

Homework Statement


A small plane flying into the wind takes 3 h 20 min to complete a flight of 960km. Flying with the wind, the same plane takes 2 h 30 mins to make the trip. What is the speed of the plane? What is the speed of the wind?


Homework Equations


N/A

The Attempt at a Solution


I'm unsure on how to set-up the two equations:

Let x represent the speed of the plane and y represent the speed of the wind.

7/3(x-y)=960

5/2(x+y)=960

Is this representation correct?

Looks good to me. Now solve for x and y.
 
  • #3
Mark44 said:
Looks good to me. Now solve for x and y.
EDIT: The mistake is 7/3; it is suppose to be 10/3.

Rewriting:

10x-10y=2880

5x+5y=1920

or

5x-5y=1440

5x+5y=1920

10x=3360

x=336

Substituting:

5(336)+5y=1920

1680+5y=1920

y=48
 
Last edited:
  • #4
Sorry, I didn't notice before, but 3hr 20 min = 10/3 hr, not 7/3 hr.
 
  • #5
Mark44 said:
Sorry, I didn't notice before, but 3hr 20 min = 10/3 hr, not 7/3 hr.

Thanks :smile:.
 

1. What are systems of equations?

Systems of equations are a set of equations with multiple variables that are solved simultaneously to find the values of each variable. They are used to model real-world situations and can have one or more solutions.

2. How are systems of equations used to solve word problems?

Word problems involve real-world scenarios that can be modeled using systems of equations. By setting up and solving the equations, we can find the values of the variables that represent the unknown quantities in the problem.

3. What is the difference between a consistent and an inconsistent system of equations?

A consistent system of equations has at least one solution, meaning the graphs of the equations intersect at a point. An inconsistent system has no solution, meaning the graphs are parallel and never intersect.

4. How do you know when to use substitution or elimination to solve a system of equations?

If one of the equations has a variable with a coefficient of 1 or -1, substitution may be the best method. If the coefficients of one variable in both equations are the same or opposite, elimination may be the best method. It is also helpful to consider the number of variables and equations in the system.

5. Can systems of equations be used to solve any type of word problem?

Systems of equations can be used to solve many types of word problems, but not all. They are most commonly used for problems involving two or three unknown quantities that can be represented by two or three equations. If the problem has more than three unknown quantities, it may be more efficient to use other methods such as matrices or linear programming.

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